International Journal of Speech-Language Pathology
ISSN: 1754-9507 (Print) 1754-9515 (Online) Journal homepage: http://www.tandfonline.com/loi/iasl20
Prevalence of stuttering in primary school children in Cairo-Egypt Mahmoud Abou Ella, Marwa Saleh, Ihab Habil, Mohammed El Sawy & lamia El Assal To cite this article: Mahmoud Abou Ella, Marwa Saleh, Ihab Habil, Mohammed El Sawy & lamia El Assal (2015) Prevalence of stuttering in primary school children in Cairo-Egypt, International Journal of Speech-Language Pathology, 17:4, 367-372, DOI: 10.3109/17549507.2015.1010583 To link to this article: http://dx.doi.org/10.3109/17549507.2015.1010583
Published online: 05 Mar 2015.
Submit your article to this journal
Article views: 48
View related articles
View Crossmark data
Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=iasl20 Download by: [University of Birmingham]
Date: 10 November 2015, At: 13:46
International Journal of Speech-Language Pathology, 2015; 17(4): 367–372
Prevalence of stuttering in primary school children in Cairo-Egypt Mahmoud Abou Ella, Marwa Saleh, Ihab Habil, Mohammed El Sawy & lamia El Assal
Downloaded by [University of Birmingham] at 13:46 10 November 2015
Ain Shams Faculty of Medicine, Cairo, Egypt
Abstract Purpose: To determine the prevalence of stuttering among primary school children in Cairo. Method: A cross-sectional design was employed. Using a multi-stage random sample from 10 schools in Cairo, a total of 8765 primary school students were enrolled in the study. The teacher referring method was initially used to detect stuttering students, which was then confirmed by a Speech Language Pathologist (SLP) using Diagnostic and Statistical Manual for Mental Disorders–Fourth Edition (DSM-IV) criteria. Personal data were collected for all students and separate questionnaires were administered to the parents of each stuttering child, inquiring about consanguinity, family history, presence of other disorders and family attitudes towards the child. Result: Prevalence of stuttering among primary school children in Cairo was 1.03%. The prevalence of stuttering showed a declining trend in the older age group. Stuttering was 7-fold more prevalent among left-handed students. Males had a higher prevalence of stuttering, but didn’t reach statistical significance. Anxiety was expressed in 25% of the families of affected children. Positive family history was found in 28% of cases, mainly among first-degree relatives. Conclusion: The current study showed a prevalence of stuttering comparable to other areas of the world with some evidence of hereditary background, although lower than that reported by other studies.
Keywords: Prevalence, stuttering, school children, Cairo
Introduction Stuttering has affected people from all cultures for at least 40 centuries and there has been controversy for decades concerning its definitions, methods of assessment and its treatment. Stuttering is a disorder of the neuro-motor control of speech, influenced by the interactive process of language production and intensified by the learning process (Peters & Guitar, 1991). According to the American Speech-LanguageHearing Association (ASHA, 1999), fluency disorders are defined as a deviation in the continuity, smoothness, rhythm and/or effort with which language units are spoken. The cumulative incidence of stuttering in the pre-school years is ∼ 11% (Reilly, Onslow, Packman, Cini, Conway, Ukoumunne, et al., 2013), while the lifetime incidence of stuttering is estimated at 4–5% compared to its point prevalence of 0.5–1% (Felsenfeld, 2002). The onset of stuttering in 85% of cases occurs by the age of 3.5 years, and children past age 4 face a relatively low risk for stuttering, with rates of natural, unassisted recovery of nearly 75% up to the age of 10–12 years (Yairi & Ambrose, 2005). This natural recovery explains the discrepancy between the cumu-
lative incidence and point prevalence rates. Epidemiological studies reveal a higher prevalence of stuttering in pre-school children, approaching 2–3% in the age group 2–5 years (McLeod & Harrison, 2009; Okalidou & Kampanaros, 2001; Proctor, Yairi, & Duff, 2008) and decreasing over the years to be lowest in adults (less than 0.5%) (Craig, Hancock, Tran, Craig, & Peters K, 2002; McKinnon, McLeod, & Reilly, 2007; Mohamadi, Nilipour, & Yadegari, 2008). Prevalence studies of stuttering in school children show some variability in terms of prevalence rates. Among the studies carried out in the last 3 decades, the highest prevalence rate was reported by Boyle, Boulet, Schieve, Cohen, Blumberg, Yeargin-Allsopp, et al. (2001) in a large study in the US. They used the reports of guardians and parents to determine the presence of stuttering among 119,367 subjects aged 3–17 years enrolled in the study. The prevalence rate of stuttering was 1.99% in the age group 3–10 years and 1.15% in the age group 11–17 years. One small study carried out in Sydney on 437 school students aged 5–12 years reported a comparable prevalence rate of 1.8%, using direct assessment to determine stuttering (Harasty & Reed, 1994); however, this
Correspondence: Dr Ihab Habil, Ain Shams Faculty of Medicine, Cairo, Egypt. Email: [email protected] ISSN 1754-9507 print/ISSN 1754-9515 online © 2015 The Speech Pathology Association of Australia Limited Published by Informa UK, Ltd. DOI: 10.3109/17549507.2015.1010583
Downloaded by [University of Birmingham] at 13:46 10 November 2015
368 M. Abouel Ella et al. study was criticized for its small sample size. Craig et al. (2002) reported a prevalence rate of 1.44% in the age group 6–10 years in a study on 12,131 subjects in Australia. This study encompassed a wider age group, from less than 1 year up to 99 years, and used affirmative tape recording to determine stuttering after a screening telephone interview. Another study carried out in Belgium in 2006 on 21,027 subjects aged 6–20 years revealed a much lower prevalence rate of 0.78% for the age group 6–10 years and a total prevalence rate of 0.58%. This study made use of a questionnaire distributed to teachers (Van Borsel, Moeyaert, Mostaert, Rosseel, Van Loo, & Van Renterghem, 2006). The lowest prevalence of stuttering recorded recently was in the study by McKinnon et al. (2007). This study was conducted in Australia on 10,000 children from kindergarten up to grade 6. The study used trained teachers for referral of stuttering children, followed by direct examination. The prevalence rate in this study was 0.33%. In the Middle East, two studies were published recently in Iran. One study from 2005 examined 7881 students in primary schools using face-to-face interviews and found the prevalence rate of stuttering to be 1.2% (Karbasi, Fallah, & Golestan, 2011). A second study carried out in 2007 on children aged 6–19 years, speaking bilingual Kurdish and Farsi, revealed a higher rate of 2% in primary school children, which decreased to 0.5% in high school children. The latter study used a teacher referral method followed by direct assessment (Mohamadi et al., 2008). In Egypt, very scarce data are available concerning the epidemiology of stuttering. One study, carried out in 1974, enrolled 8459 school children aged 6–12 years from governmental and private schools in Eastern Cairo. School records and personal interviews were the tools used to determine stuttering. The prevalence rate in this study was 0.93% (Okasha, Bishry, Kamel, & Hassan, 1974). It is often reported that stuttering affects people’s lives in a number of contexts, including education, employment, and psychological well-being (Klompas & Ross, 2004; McAllister, Collier, & Shepstone, 2013). Epidemiological data are valuable for estimating the proportion of population who might be at risk for these types of sequelae and estimating resources needed to support individuals who stutter through these challenges throughout their childhood and adolescence. Some research has found a negative association between educational achievement and stuttering severity (O’Brian, Jones, Packman, Menzies, & Onslow, 2011), as well as negative peer behaviour, including bullying, which hinders school attendance and academic achievement (Langevin, Packman, & Onslow, 2009). McAllister, Collier, and Shepstone (2012), in a secondary analysis of a British cohort dataset, reported that stuttering children exhibit poorer cognitive test scores and have been bullied, although the final educational outcome was not significantly
affected. In the same study, people who stutter reported having lower-status jobs. Researchers have pointed out that persons who stutter experience disabling levels of social anxiety (Messenger, Onslow, Packman, & Menzies, 2004) and poor mental health (McAllister et al., 2013). Overall, stuttering has a negative impact on the quality-of-life (Koedoot, Bouwmans, Franken, & Stolk, 2011). In view of the scarce available data on the epidemiology of stuttering in Egypt, the aim of the current study was to determine the prevalence of stuttering among primary school children in Cairo. Methods This study is a cross-sectional study carried out in primary schools in Egypt. Participants A total of 8765 students were enrolled in the study using multi-stage random sampling. Cairo was divided into five regions (South, North, East, West and New District areas) and then two schools from each region were selected. The first school in each region was governmental and the second was a private school. Governmental schools are free compared to the paid private schools, which may cause variation in the student population in each category. Accordingly, representative samples from governmental and public schools were selected to ensure representation of different socio-economic classes. All schools were mixed schools (for both boys and girls) for normal students. Schools were chosen by simple random sampling. All primary students in the selected school were enrolled in the study. Five children referred by teachers were eliminated from the study as their parents did not consent to further assessment. Procedures Diagnosis of stuttering among the students was carried out in two steps: the teacher referral method (Keating, Turrell, & Ozanne, 2001) was used initially, whereby the teacher referred potential stutterers from his/her class; then a speech-language pathologist (SLP) with 10 years’ experience confirmed the diagnosis by interviewing the child. During the personal interview, a 30–45 minute conversation with the student was carried out; this was partly spontaneous and partly elicited by pictures. Diagnosis of stuttering was made using the Diagnostic and Statistical Manual for Mental Disorders–Fourth Edition (DSM-IV) criteria. The DSM-IV criteria for diagnosing stuttering are disturbance in the normal fluency and time patterning of speech (inappropriate for the individual’s age) that interferes with academic or occupational achievement or with social communication and, if a speech-motor or sensory deficit is present, the speech difficulties are in excess of those usually associated with these problems.
Stuttering in school children in Egypt 369
Table I. Characteristics of the study sample (total n 8765). Study Sample, n (%)
Downloaded by [University of Birmingham] at 13:46 10 November 2015
Sex Male Female Age group 7–9 years 10 years 11 years 12 years
5812 (66.31) 2953 (33.69) 4521 1426 1347 1469
(51.58) (16.29) (15.37) (16.76)
Two questionnaires were used: the first was a general demographic questionnaire administered to all students to assess sex, age, grade and dominant hand. The second questionnaire was administered to parents of stuttering students and inquired about consanguinity, family history, as well as direct questions about feelings of anxiety by the family. Ethical considerations The protocol of the study was approved by the Ethical Research Committee of Ain Shams Faculty of Medicine. Approval from the administrative authorities of the selected schools was obtained before carrying out the research. Consent was obtained from parents of affected children and all data were handled anonymously. Statistical analysis Data were analysed using SPSS version 15 and Epiinfo version 6; the data were presented in frequency and related percentage. Comparison of qualitative data was done using the Chi-square test. The prevalence ratio with 95% confidence interval (CI) was calculated for the factors associated with stuttering. The Chi-square for trend was calculated to verify a significant trend in the prevalence of stuttering across age. A p-value of 0.05 was set as the level of significance.
Results This study was carried out on primary school children aged 7–12 years. Males composed almost two thirds of the whole study sample (Table I). The overall prevalence of stuttering in the study group was 1.03%. Prevalence of stuttering was slightly higher in males, but this difference did not reach statistical significance. The prevalence of stuttering showed a progressive decline with older age (Chi-square for trend 4.4, p 0.035). Left-handed students showed more stuttering, almost 7-fold more than right-handed students (Table II). As shown in Table III, almost one quarter of families with stuttering children expressed feelings of anxiety. Behaviours accompanying stuttering are described in Table III. The current study revealed a prominent hereditary background among the stuttering children. Consanguinity was prevalent in 20% of stuttering cases. The affected family member was present in 28% of cases and the affected member was mainly a first-degree relative. Among the first-degree relatives affected, eight cases were reported in the father compared to four cases in the mother. This differential was not observed among second-degree relatives, where cases were evenly divided between paternal and maternal relatives. However, all affected second-degree relatives were male. Eight identical twins were encountered among stuttering children and both children were affected in five of them (Table IV). Discussion The current study found that the prevalence of stuttering among 8765 primary school children in Cairo was 1.03%. While reported prevalence rates of stuttering among school children have varied in the few published studies, some studies have reported comparable results to the current study. In Iran, the prevalence of stuttering among elementary school children was reported as 1.2 among 7881 students
Table II. Prevalence of stuttering in the study group (total n 8765). n (%) Overall prevalence Age group 7–9 years 10 years 11 years 12 years Sex Male Female Dominant hand Right handed Left handed * c2 for trend 4.4. **Prevalence ratio.
90 (1.03) 95% CI (0.83–1.25) 56 13 11 10
p-value
PR** (95% CI)
0.035*
(1.24) (0.91) (0.82) (0.68) 0.233
65 (1.18) 25 (0.85)
1.32 (0.83–2.09) 1 0.001
67 (0.79) 23 (6.07)
1 7.6 (4.78–12.06)
370 M. Abouel Ella et al. Table III. Family perception and personal accompanying disorders in the group of individuals who stutter (n 90).
Downloaded by [University of Birmingham] at 13:46 10 November 2015
Anxiety feeling in the family Stuttering accompanying disorders Stuttering in automatic speech Presence of involuntary movement Presence of interjections Speaks in monotone Presence of cluttering
n (n 90)
Percentage
23
25.56%
47 34 31 10 15
52.22% 37.78% 34.44% 11.11% 16.67%
(Karbasi et al., 2011), similar to our results. However, another study reported a higher prevalence of 2% (Mohamadi et al., 2008), but this was for bilingual children, a condition suspected to increase the prevalence of stuttering, although the literature is inconsistent (Au-Yeung, Howell, Charles, & Sackin, 2000). In Egypt, one study carried out by Okasha et al. (1974) reported a stuttering prevalence of 0.93% among 8459 primary school children, using school records and direct assessment as methods of research. Although this study was published relatively long ago and was carried out in Eastern Cairo only, not covering other districts in the Egyptian capital, this earlier study in Egypt reported a similar rate of prevalence as the current study. Other prevalence studies have reported different prevalence rates from ours. Craig et al. (2002) reported a prevalence of ∼ 1.4% among a sample of Australian children in the age group 6–10 years; the researchers used telephone interview with tape recording to determine stuttering. In Belgium, the prevalence of stuttering was assessed using questionnaires distributed to the teachers. The reported prevalence for age 6–10 years was 0.78%, which is lower than our finding (Van Borsel et al., 2006). The study of McKinnon et al. (2007) reported the lowest prevalence rate of 0.33 among school children up to grade 6. The researchers assessed stuttering as well as other speech disorders using a strict 4-stage process: training in the data collection process, teacher identification, confirmation by a speech-language pathologist and consultation with district special needs advisors. Table IV. Hereditary characteristics of stuttering in the group of individuals who stutter (n 90).
Consanguinity Positive family member First relativea Second relativeb First and second relatives Third relative affection Affected identical twin
n/total
Percentage
18/90 28/90 20/28 1/28 5/28 2/28 5/8
20.00% 31.11% 71.43% 3.57% 17.86% 7.14% 62.50%
a Among the first degree relatives, 13 cases occurred in parents: eight in the father and four in the mother and one case in both. bAmong six cases with 2nd degree relatives, three cases occurred in the mother’s side and three cases in the father’s side.
It is likely that the different findings among different studies may be related to the methods used to identify the presence of stuttering (Yairi & Ambrose, 2013). Although cross-country differences cannot be neglected, the lack of a standardized, objective tool to determine stuttering, together with the variation in stuttering definition, may be one particular factor behind the difference in reported prevalence rates. However, apart from the results of McKinnon et al., it seems that the prevalence of stuttering tends toward 1% in children. The current study showed progressive decline in the prevalence of stuttering as students age. The prevalence of stuttering started with 1.2% in the youngest school children (7–9 years) and ended with 0.7% in children aged 12 years (Table II). Similar findings have been observed in many studies. McKinnon et al. (2007) reported a prevalence of stuttering of ∼ 0.6% in grade 1 of primary school, with progressive decline to 0.07% in grade 5. It should be noted that the total prevalence of stuttering reported in the study of McKinnon et al. was 0.33 in primary school children—almost a third less than our finding—which in turn may explain the discrepancy in prevalence observed in the two studies at different grade levels. It is generally accepted that stuttering often starts by age 2–4 years, coinciding with language development, particularly the use of 2–3 word phrases (Reilly, Onslow, Packman, Wake, Bavin, Prior, et al., 2009). Longitudinal studies on stuttering show a spontaneous recovery rate of 65–80% up to the teenage years, but decreasing significantly if the problem persists after 16 years (Dworzynski, Remington, Rijksdijk, Howell, & Plomin, 2007). This phenomenon is most likely the reason for the lower prevalence observed with progressing age. Sex has been reported as one of the factors linked to stuttering. Studies have pointed out that the disorder affects males more than females, especially in adults (Yairi & Ambrose, 2013). The sex (male/female) differential is smaller in pre-school children, ∼ 2/1 or less, and gradually increases with age to become 3/1 or even 5/1 in adults (Craig et al., 2002; Yairi & Ambrose, 1999). The current study showed that the prevalence of stuttering was 1.32-times higher in males than females. Although statistically insignificant, the trend is inclined towards male predominance. The observed stuttering sex ratio in the current study is less than the doubled or tripled male risk reported in other studies (Craig et al., 2002; Yairi & Ambrose, 1999). One study carried out in Iran, a country with comparable social and cultural characteristics to Egypt, revealed a sex ratio for stuttering of 1.29 in elementary school (Mohamadi et al., 2008). This finding is almost identical to our result. The apparent difference between our results and the Iranian study, compared to other studies in developed countries, may suggest a true racial effect or a social factor that hinders female education, which then leads to under-representation
Downloaded by [University of Birmingham] at 13:46 10 November 2015
of the female population in school samples. Such a situation was encountered in our study where females represented only one third of the sample. Another aspect revealed in the current study is the relation of the dominant hand to stuttering. Stuttering was 7-times more prevalent in left-handed than right-handed students (Table II). Individual hand preference has not been extensively studied in developmental stuttering, despite the long-standing hypothesis that developmental stuttering may be associated with atypical cerebral laterality. Atypical hand preference may be a marker of atypical cerebral laterality or atypical brain dominance. Left-handed individuals have been reported to show more stuttering (Bryngelson & Clark, 1993) as well as greater tendency to chronic stuttering (Brosch, Haege, Kalehne, & Johannsen, 1999). Stuttering is often perceived as a stigmatizing disorder for both the child and the family. Studies have shown that most families are affected by their child’s stuttering. The most frequently reported reactions are worry/anxiety/concern, uncertainty about what to do and frustration (Langevin, Packman, & Onslow, 2010). The current study showed that almost one quarter of families of affected children expressed anxiety regarding their child’s stuttering (Table III). Whether or not this result is an under-estimate, as many parents may deny any reaction towards the disorder, it points to a considerable effect on the families of affected children. Growing evidence supports a link between genetics and stuttering (Ambrose, Yairi, & Cox, 1993; Yairi, Ambrose, & Cox, 1996), and it has been the focus of research since the 1930s. There are many approaches to studying the genetic contribution to stuttering, including twin studies, family aggregation, and recent biological genetic studies. Recent twin studies confirm a strong genetic contribution to stuttering. In the Netherlands, van Beijsterveldt, Felsenfeld, and Boomsma (2010) looked at 10,500 5-year-old Dutch twin pairs. In this study, concordance for probable stuttering across sexes was 57% in monozygotic vs 31% for dizygotic pairs. In Japan, Ooki (2005) investigated a similar size sample of 1896 twin pairs. Concordance for stuttering in monozygotic pairs was 52%, but only 12% in dizygotic pairs. A recent Australian study concluded that ∼ 70% of the variance in liability for stuttering was attributable to additive genetic effects, the remainder being due to environmental effects (Felsenfeld, Kirk, Zhu, Statham, Neale, & Martin, 2000). Although the current study is not a twin study, it showed the presence of stuttering in five out of eight identical twin pairs, representing 62%, a figure close to that published in the aforementioned literature. One well-known family aggregation study carried out in the 1960s showed that the incidence of stuttering among first-degree relatives was 13.65%, substantially above the expected 5% for the general
Stuttering in school children in Egypt 371
population, with male relatives having a risk more than double that of females (Kay, 1964). A subsequent study used a sample drawn from the families of 69 pre-school children recruited soon after stuttering onset, before natural recovery had taken place. This study reported a family history of stuttering in more than two thirds of the sample, especially among first- and second-degree relatives, and confirmed the differential distribution of stuttering among male relatives (Ambrose et al., 1993). In 2005, Yairi and Ambrose reported a positive family history of stuttering for 69% of 123 families studied. Compared with the above-mentioned studies, the current study revealed a lower percentage with positive family history (28%). However, it showed male predominance in the relatives affected, in accordance with the studies of Kay and Ambrose et al. The discrepancy between the family history of 28% found in our study and the 70% reported in other studies can be explained in two ways: families may deny any family history of stuttering as they may perceive this disorder as stigmatizing, especially in our Middle Eastern culture; or they may have just replied according to their belief as they were unaware of the genetic background of the disorder, thus yielding an under-estimated proportion. One study conducted in Egypt with 100 parents of stuttering children revealed that only 8% of them thought stuttering had a genetic origin and ∼ 40% of them felt disappointed or did not accept their child’s disorder (Safwat & Sheikhany, 2014), which supports the above explanation. The current study highlighted the underresearched problem of stuttering in school children in Cairo. The finding of a prevalence rate of 1.03% is similar to that observed in other areas in the world. The prevalence of stuttering was observed to decrease with advancing age. Stuttering was more common among left-handed children and trended higher among males, although this latter result was not significant. The findings show that stuttering affects families, with evidence of hereditary origin.
Acknowledgement The authors express their great thanks to the administrative authorities of selected schools for their support in carrying out this research as well to children and their families who participated in the study. This research was approved by the Ethical research Committee of Ain shams Faculty of Medicine and was not funded by any national or international agency. Declaration of Interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.
372 M. Abouel Ella et al.
Downloaded by [University of Birmingham] at 13:46 10 November 2015
References Ambrose, N. G., Yairi, E., & Cox, N. (1993). Genetic aspects of early childhood stuttering. Journal of Speech, Language, and Hearing Research, 36, 701–706. American Speech-Language-Hearing Associations (ASHA). (1999). Terminology pertaining to fluency and fluency disorders: guidelines ASHA; supplement No. 19, 41-2,29–36. Au-Yeung, J., Howell, P., Charles, N., & Sackin, S. (2000). UCL survey of bilingualism and stuttering. In Bosshardt, H. -G. G., Yaruss, S., Peters, H., (Eds.), Proceedings of the 3rd World Congress on Fluency Disorders (p. 129–132). Nijmegen: Nijmegen University Press. Boyle, C., Boulet, S., Schieve, L., Cohen, R., Blumberg, S., Yeargin-Allsopp, M., et al. (2001). Trends in the Prevalence of Developmental Disabilities in US Children, 1997–2008. Pediatrics, 34, 385–395. Brosch, S., Haege, A., Kalehne, P., & Johannsen, H. S. (1999). Stuttering children and the probability of remission—the role of cerebral dominance and speech production. International Journal of Pediatric Otorhinolaryngolology, 47, 71–76. Bryngelson, B., & Clark, T. (1993). Left-handedness and stuttering. Journal of Heredity, 24, 387–390. Craig, A., Hancock, K., Tran, V., Craig, M., & Peters, K. (2002). Epidemiology of stuttering in the community across the entire life span. Journal of Speech, Language, and Hearing Research, 45, 1097–1105. Dworzynski, K., Remington, A., Rijksdijk, F., Howell, P., & Plomin, R. (2007). Genetic etiology in cases of recovered and persistent stuttering in an unselected longitudinal sample of young twins. American Journal of Speech-Language Pathology, 16, 167–178. Felsenfeld, S. (2002). Finding susceptibility genes for developmental disorders of speech: The long and winding road. Journal of Communication Disorders, 35, 329–345. Felsenfeld, S., Kirk, K. M., Zhu, G., Statham, D. J., Neale, M. C., & Martin, N. G. (2000). A study of the genetic and environmental etiology of stuttering in a selected twin sample. Behavior Genetics, 30, 359–366. Harasty, J., & Reed, V. (1994). The prevalence of speech and language impairment in two Sydney metropolitanschools: A summary and critical review. Australian Journal of Human Communication Disorders, 22, 63–80. Karbasi, S. A., Fallah, R., & Golestan, M. (2011). The prevalence of speech disorder in primary school students in Yazd-Iran. Acta Medica Iranica, 49, 33–37. Kay, D. (1964). The genetics of stuttering. In G., Andrews, & M., Harris, (Eds.), The Syndrome of Stuttering (pp 132–143). London: The Spastic Society Medical Education and Information Unit. Keating, D., Turrell, G., & Ozanne, A. (2001). Childhood speech disorders: Reported prevalence, comorbidity and socioeconomic profile. Journal of Paediatrics and Child Health, 37, 431–436. Klompas, M., & Ross, E. (2004). Life experiences of people who stutter, and the perceived impact of stuttering on quality of life: Personal accounts of South African individuals. Journal of Fluency Disorders, 29, 275–305. Koedoot, C., Bouwmans, C., Franken, M., & Stolk, E. (2011). Quality of life in adults who stutter. Journal of Communication Disorders, 44, 429–443. Langevin, M., Packman, A., & Onslow, M. (2009). Peer responses to stuttering in the preschool setting. American Journal of Speech Language Pathology, 18, 264–276. Langevin, M., Packman, A., & Onslow, M. (2010). Parent perceptions of the impact of stuttering on their preschoolers and themselves. Journal of Communication Disorders, 43, 407–423. McAllister, J., Collier, J., & Shepstone, L. (2012). The impact of adolescent stuttering on educational and employment outcomes: Evidence from a birth cohort study. Journal of Fluency Disorders, 37, 106–121.
McAllister, J., Collier, J., & Shepstone, L. (2013). The impact of adolescent stuttering and other speech problems on psychological well-being in adulthood: evidence from a birth cohort study. International Journal of Language & Communication Disorders, 48, 458–468. McKinnon, D., McLeod, S., & Reilly, S. (2007). The Prevalence of Stuttering, Voice, and Speech-Sound Disorders in Primary School Students in Australia. Language, Speech, and Hearing Services in Schools, 38, 5–15. McLeod, S., & Harrison, L. (2009). Epidemiology of speech and language impairment in a nationally representative sample of 4- to 5-year-old children. Journal of Speech, Language, and Hearing Research, 52, 113–129. Messenger, M., Onslow, M., Packman, A., & Menzies, R. (2004). Social anxiety in stuttering: Measuring negative social expectancies. Journal of Fluency Disorders, 29, 201–212. Mohamadi, H., Nilipour, R., & Yadegari, F. (2008). Stuttering prevalence among Kurdish-Farsi students; Effects of the two languages similarities. Iranian Rehabilitation Journal, 6, 83–88. O’Brian, S., Jones, M., Packman, A., Menzies, R., & Onslow, M. (2011). Stuttering severity and educational attainment. Journal of Fluency Disorders, 36, 86–92. Okalidou, A., & Kampanaros, M. (2001). Teacher perceptions of communication impairment at screening stage in preschool children living in Patras, Greece. International Journal of Language & Communication Disorders, 36, 489–502. Okasha, A., Bishry, Z., Kamel, M., & Hassan, A. H. (1974). Psychosocial study of stammering in Egyptian children. British Journal of Psychiatry, 124, 534–535. Ooki, S. (2005). Genetic and environmental influences on stuttering and tics in Japanese children. Twin Research and Human Genetics, 8, 69–75. Peters, T. J., & Guitar, B. (1991). Stuttering an integrated approach to its nature and treatment. Baltimore, MD: Williams & Wilkins. Proctor, A., Yairi, E., & Duff, M. (2008). Prevalence of stuttering in African American preschool children. Journal of Speech, Language, and Hearing Research, 50, 1465–1474. Reilly, S., Onslow, M., Packman, A., Cini, E., Conway, L., Ukoumunne, O. C., et al. (2013). Natural History of Stuttering to 4 Years of Age: A Prospective Community – Based Study. Pediatrics, 132, 460–467. Reilly, S., Onslow, M., Packman, A., Wake, M., Bavin, E. L., Prior, M., et al. (2009). Predicting Stuttering Onset by the Age of 3 Years: A Prospective, Community Cohort Study. Pediatrics, 123, 270–277. Safwat, R. F., & Sheikhany, A. (2014). Parental attitudes and knowledge of stuttering. The Egyptian Journal of Otolaryngology, 30, 151–156. Van Beijsterveldt, C. E. M., Felsenfeld, S., & Boomsma, D. I. (2010). Bivariate genetic analysis of stuttering and non fluency in a large sample of 5-year-old twins. Journal of Speech, Language, and Hearing Research, 53, 609–619. Van Borsel, J., Moeyaert, J., Mostaert, C., Rosseel, R., Van Loo, E., & Van Renterghem, T. (2006). Prevalence of stuttering in regular and special school populations in Belgium based on teacher perceptions. Folia Phoniatrica et Logopaedica, 58, 289–302. Yairi, E., & Ambrose, N. G. (1999). Early childhood stuttering I: persistency and recovery Journal of Speech, Language, and Hearing Research, 42,1097–1112. Yairi, E., & Ambrose, N. G. (2005). Early Childhood Stuttering. Austin, TX: Pro Ed. Yairi, E., & Ambrose, N. G. (2013). Epidemiology of Stuttering: 21st Century Advances. Journal of Fluency Disorders, 38, 66–87. Yairi, E., Ambrose, N. G., & Cox, N. (1996). Genetics of stuttering: A critical review. Journal of Speech, Language, and Hearing Research, 39,771–784.
ISSN: 1754-9507 (Print) 1754-9515 (Online) Journal homepage: http://www.tandfonline.com/loi/iasl20
Prevalence of stuttering in primary school children in Cairo-Egypt Mahmoud Abou Ella, Marwa Saleh, Ihab Habil, Mohammed El Sawy & lamia El Assal To cite this article: Mahmoud Abou Ella, Marwa Saleh, Ihab Habil, Mohammed El Sawy & lamia El Assal (2015) Prevalence of stuttering in primary school children in Cairo-Egypt, International Journal of Speech-Language Pathology, 17:4, 367-372, DOI: 10.3109/17549507.2015.1010583 To link to this article: http://dx.doi.org/10.3109/17549507.2015.1010583
Published online: 05 Mar 2015.
Submit your article to this journal
Article views: 48
View related articles
View Crossmark data
Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=iasl20 Download by: [University of Birmingham]
Date: 10 November 2015, At: 13:46
International Journal of Speech-Language Pathology, 2015; 17(4): 367–372
Prevalence of stuttering in primary school children in Cairo-Egypt Mahmoud Abou Ella, Marwa Saleh, Ihab Habil, Mohammed El Sawy & lamia El Assal
Downloaded by [University of Birmingham] at 13:46 10 November 2015
Ain Shams Faculty of Medicine, Cairo, Egypt
Abstract Purpose: To determine the prevalence of stuttering among primary school children in Cairo. Method: A cross-sectional design was employed. Using a multi-stage random sample from 10 schools in Cairo, a total of 8765 primary school students were enrolled in the study. The teacher referring method was initially used to detect stuttering students, which was then confirmed by a Speech Language Pathologist (SLP) using Diagnostic and Statistical Manual for Mental Disorders–Fourth Edition (DSM-IV) criteria. Personal data were collected for all students and separate questionnaires were administered to the parents of each stuttering child, inquiring about consanguinity, family history, presence of other disorders and family attitudes towards the child. Result: Prevalence of stuttering among primary school children in Cairo was 1.03%. The prevalence of stuttering showed a declining trend in the older age group. Stuttering was 7-fold more prevalent among left-handed students. Males had a higher prevalence of stuttering, but didn’t reach statistical significance. Anxiety was expressed in 25% of the families of affected children. Positive family history was found in 28% of cases, mainly among first-degree relatives. Conclusion: The current study showed a prevalence of stuttering comparable to other areas of the world with some evidence of hereditary background, although lower than that reported by other studies.
Keywords: Prevalence, stuttering, school children, Cairo
Introduction Stuttering has affected people from all cultures for at least 40 centuries and there has been controversy for decades concerning its definitions, methods of assessment and its treatment. Stuttering is a disorder of the neuro-motor control of speech, influenced by the interactive process of language production and intensified by the learning process (Peters & Guitar, 1991). According to the American Speech-LanguageHearing Association (ASHA, 1999), fluency disorders are defined as a deviation in the continuity, smoothness, rhythm and/or effort with which language units are spoken. The cumulative incidence of stuttering in the pre-school years is ∼ 11% (Reilly, Onslow, Packman, Cini, Conway, Ukoumunne, et al., 2013), while the lifetime incidence of stuttering is estimated at 4–5% compared to its point prevalence of 0.5–1% (Felsenfeld, 2002). The onset of stuttering in 85% of cases occurs by the age of 3.5 years, and children past age 4 face a relatively low risk for stuttering, with rates of natural, unassisted recovery of nearly 75% up to the age of 10–12 years (Yairi & Ambrose, 2005). This natural recovery explains the discrepancy between the cumu-
lative incidence and point prevalence rates. Epidemiological studies reveal a higher prevalence of stuttering in pre-school children, approaching 2–3% in the age group 2–5 years (McLeod & Harrison, 2009; Okalidou & Kampanaros, 2001; Proctor, Yairi, & Duff, 2008) and decreasing over the years to be lowest in adults (less than 0.5%) (Craig, Hancock, Tran, Craig, & Peters K, 2002; McKinnon, McLeod, & Reilly, 2007; Mohamadi, Nilipour, & Yadegari, 2008). Prevalence studies of stuttering in school children show some variability in terms of prevalence rates. Among the studies carried out in the last 3 decades, the highest prevalence rate was reported by Boyle, Boulet, Schieve, Cohen, Blumberg, Yeargin-Allsopp, et al. (2001) in a large study in the US. They used the reports of guardians and parents to determine the presence of stuttering among 119,367 subjects aged 3–17 years enrolled in the study. The prevalence rate of stuttering was 1.99% in the age group 3–10 years and 1.15% in the age group 11–17 years. One small study carried out in Sydney on 437 school students aged 5–12 years reported a comparable prevalence rate of 1.8%, using direct assessment to determine stuttering (Harasty & Reed, 1994); however, this
Correspondence: Dr Ihab Habil, Ain Shams Faculty of Medicine, Cairo, Egypt. Email: [email protected] ISSN 1754-9507 print/ISSN 1754-9515 online © 2015 The Speech Pathology Association of Australia Limited Published by Informa UK, Ltd. DOI: 10.3109/17549507.2015.1010583
Downloaded by [University of Birmingham] at 13:46 10 November 2015
368 M. Abouel Ella et al. study was criticized for its small sample size. Craig et al. (2002) reported a prevalence rate of 1.44% in the age group 6–10 years in a study on 12,131 subjects in Australia. This study encompassed a wider age group, from less than 1 year up to 99 years, and used affirmative tape recording to determine stuttering after a screening telephone interview. Another study carried out in Belgium in 2006 on 21,027 subjects aged 6–20 years revealed a much lower prevalence rate of 0.78% for the age group 6–10 years and a total prevalence rate of 0.58%. This study made use of a questionnaire distributed to teachers (Van Borsel, Moeyaert, Mostaert, Rosseel, Van Loo, & Van Renterghem, 2006). The lowest prevalence of stuttering recorded recently was in the study by McKinnon et al. (2007). This study was conducted in Australia on 10,000 children from kindergarten up to grade 6. The study used trained teachers for referral of stuttering children, followed by direct examination. The prevalence rate in this study was 0.33%. In the Middle East, two studies were published recently in Iran. One study from 2005 examined 7881 students in primary schools using face-to-face interviews and found the prevalence rate of stuttering to be 1.2% (Karbasi, Fallah, & Golestan, 2011). A second study carried out in 2007 on children aged 6–19 years, speaking bilingual Kurdish and Farsi, revealed a higher rate of 2% in primary school children, which decreased to 0.5% in high school children. The latter study used a teacher referral method followed by direct assessment (Mohamadi et al., 2008). In Egypt, very scarce data are available concerning the epidemiology of stuttering. One study, carried out in 1974, enrolled 8459 school children aged 6–12 years from governmental and private schools in Eastern Cairo. School records and personal interviews were the tools used to determine stuttering. The prevalence rate in this study was 0.93% (Okasha, Bishry, Kamel, & Hassan, 1974). It is often reported that stuttering affects people’s lives in a number of contexts, including education, employment, and psychological well-being (Klompas & Ross, 2004; McAllister, Collier, & Shepstone, 2013). Epidemiological data are valuable for estimating the proportion of population who might be at risk for these types of sequelae and estimating resources needed to support individuals who stutter through these challenges throughout their childhood and adolescence. Some research has found a negative association between educational achievement and stuttering severity (O’Brian, Jones, Packman, Menzies, & Onslow, 2011), as well as negative peer behaviour, including bullying, which hinders school attendance and academic achievement (Langevin, Packman, & Onslow, 2009). McAllister, Collier, and Shepstone (2012), in a secondary analysis of a British cohort dataset, reported that stuttering children exhibit poorer cognitive test scores and have been bullied, although the final educational outcome was not significantly
affected. In the same study, people who stutter reported having lower-status jobs. Researchers have pointed out that persons who stutter experience disabling levels of social anxiety (Messenger, Onslow, Packman, & Menzies, 2004) and poor mental health (McAllister et al., 2013). Overall, stuttering has a negative impact on the quality-of-life (Koedoot, Bouwmans, Franken, & Stolk, 2011). In view of the scarce available data on the epidemiology of stuttering in Egypt, the aim of the current study was to determine the prevalence of stuttering among primary school children in Cairo. Methods This study is a cross-sectional study carried out in primary schools in Egypt. Participants A total of 8765 students were enrolled in the study using multi-stage random sampling. Cairo was divided into five regions (South, North, East, West and New District areas) and then two schools from each region were selected. The first school in each region was governmental and the second was a private school. Governmental schools are free compared to the paid private schools, which may cause variation in the student population in each category. Accordingly, representative samples from governmental and public schools were selected to ensure representation of different socio-economic classes. All schools were mixed schools (for both boys and girls) for normal students. Schools were chosen by simple random sampling. All primary students in the selected school were enrolled in the study. Five children referred by teachers were eliminated from the study as their parents did not consent to further assessment. Procedures Diagnosis of stuttering among the students was carried out in two steps: the teacher referral method (Keating, Turrell, & Ozanne, 2001) was used initially, whereby the teacher referred potential stutterers from his/her class; then a speech-language pathologist (SLP) with 10 years’ experience confirmed the diagnosis by interviewing the child. During the personal interview, a 30–45 minute conversation with the student was carried out; this was partly spontaneous and partly elicited by pictures. Diagnosis of stuttering was made using the Diagnostic and Statistical Manual for Mental Disorders–Fourth Edition (DSM-IV) criteria. The DSM-IV criteria for diagnosing stuttering are disturbance in the normal fluency and time patterning of speech (inappropriate for the individual’s age) that interferes with academic or occupational achievement or with social communication and, if a speech-motor or sensory deficit is present, the speech difficulties are in excess of those usually associated with these problems.
Stuttering in school children in Egypt 369
Table I. Characteristics of the study sample (total n 8765). Study Sample, n (%)
Downloaded by [University of Birmingham] at 13:46 10 November 2015
Sex Male Female Age group 7–9 years 10 years 11 years 12 years
5812 (66.31) 2953 (33.69) 4521 1426 1347 1469
(51.58) (16.29) (15.37) (16.76)
Two questionnaires were used: the first was a general demographic questionnaire administered to all students to assess sex, age, grade and dominant hand. The second questionnaire was administered to parents of stuttering students and inquired about consanguinity, family history, as well as direct questions about feelings of anxiety by the family. Ethical considerations The protocol of the study was approved by the Ethical Research Committee of Ain Shams Faculty of Medicine. Approval from the administrative authorities of the selected schools was obtained before carrying out the research. Consent was obtained from parents of affected children and all data were handled anonymously. Statistical analysis Data were analysed using SPSS version 15 and Epiinfo version 6; the data were presented in frequency and related percentage. Comparison of qualitative data was done using the Chi-square test. The prevalence ratio with 95% confidence interval (CI) was calculated for the factors associated with stuttering. The Chi-square for trend was calculated to verify a significant trend in the prevalence of stuttering across age. A p-value of 0.05 was set as the level of significance.
Results This study was carried out on primary school children aged 7–12 years. Males composed almost two thirds of the whole study sample (Table I). The overall prevalence of stuttering in the study group was 1.03%. Prevalence of stuttering was slightly higher in males, but this difference did not reach statistical significance. The prevalence of stuttering showed a progressive decline with older age (Chi-square for trend 4.4, p 0.035). Left-handed students showed more stuttering, almost 7-fold more than right-handed students (Table II). As shown in Table III, almost one quarter of families with stuttering children expressed feelings of anxiety. Behaviours accompanying stuttering are described in Table III. The current study revealed a prominent hereditary background among the stuttering children. Consanguinity was prevalent in 20% of stuttering cases. The affected family member was present in 28% of cases and the affected member was mainly a first-degree relative. Among the first-degree relatives affected, eight cases were reported in the father compared to four cases in the mother. This differential was not observed among second-degree relatives, where cases were evenly divided between paternal and maternal relatives. However, all affected second-degree relatives were male. Eight identical twins were encountered among stuttering children and both children were affected in five of them (Table IV). Discussion The current study found that the prevalence of stuttering among 8765 primary school children in Cairo was 1.03%. While reported prevalence rates of stuttering among school children have varied in the few published studies, some studies have reported comparable results to the current study. In Iran, the prevalence of stuttering among elementary school children was reported as 1.2 among 7881 students
Table II. Prevalence of stuttering in the study group (total n 8765). n (%) Overall prevalence Age group 7–9 years 10 years 11 years 12 years Sex Male Female Dominant hand Right handed Left handed * c2 for trend 4.4. **Prevalence ratio.
90 (1.03) 95% CI (0.83–1.25) 56 13 11 10
p-value
PR** (95% CI)
0.035*
(1.24) (0.91) (0.82) (0.68) 0.233
65 (1.18) 25 (0.85)
1.32 (0.83–2.09) 1 0.001
67 (0.79) 23 (6.07)
1 7.6 (4.78–12.06)
370 M. Abouel Ella et al. Table III. Family perception and personal accompanying disorders in the group of individuals who stutter (n 90).
Downloaded by [University of Birmingham] at 13:46 10 November 2015
Anxiety feeling in the family Stuttering accompanying disorders Stuttering in automatic speech Presence of involuntary movement Presence of interjections Speaks in monotone Presence of cluttering
n (n 90)
Percentage
23
25.56%
47 34 31 10 15
52.22% 37.78% 34.44% 11.11% 16.67%
(Karbasi et al., 2011), similar to our results. However, another study reported a higher prevalence of 2% (Mohamadi et al., 2008), but this was for bilingual children, a condition suspected to increase the prevalence of stuttering, although the literature is inconsistent (Au-Yeung, Howell, Charles, & Sackin, 2000). In Egypt, one study carried out by Okasha et al. (1974) reported a stuttering prevalence of 0.93% among 8459 primary school children, using school records and direct assessment as methods of research. Although this study was published relatively long ago and was carried out in Eastern Cairo only, not covering other districts in the Egyptian capital, this earlier study in Egypt reported a similar rate of prevalence as the current study. Other prevalence studies have reported different prevalence rates from ours. Craig et al. (2002) reported a prevalence of ∼ 1.4% among a sample of Australian children in the age group 6–10 years; the researchers used telephone interview with tape recording to determine stuttering. In Belgium, the prevalence of stuttering was assessed using questionnaires distributed to the teachers. The reported prevalence for age 6–10 years was 0.78%, which is lower than our finding (Van Borsel et al., 2006). The study of McKinnon et al. (2007) reported the lowest prevalence rate of 0.33 among school children up to grade 6. The researchers assessed stuttering as well as other speech disorders using a strict 4-stage process: training in the data collection process, teacher identification, confirmation by a speech-language pathologist and consultation with district special needs advisors. Table IV. Hereditary characteristics of stuttering in the group of individuals who stutter (n 90).
Consanguinity Positive family member First relativea Second relativeb First and second relatives Third relative affection Affected identical twin
n/total
Percentage
18/90 28/90 20/28 1/28 5/28 2/28 5/8
20.00% 31.11% 71.43% 3.57% 17.86% 7.14% 62.50%
a Among the first degree relatives, 13 cases occurred in parents: eight in the father and four in the mother and one case in both. bAmong six cases with 2nd degree relatives, three cases occurred in the mother’s side and three cases in the father’s side.
It is likely that the different findings among different studies may be related to the methods used to identify the presence of stuttering (Yairi & Ambrose, 2013). Although cross-country differences cannot be neglected, the lack of a standardized, objective tool to determine stuttering, together with the variation in stuttering definition, may be one particular factor behind the difference in reported prevalence rates. However, apart from the results of McKinnon et al., it seems that the prevalence of stuttering tends toward 1% in children. The current study showed progressive decline in the prevalence of stuttering as students age. The prevalence of stuttering started with 1.2% in the youngest school children (7–9 years) and ended with 0.7% in children aged 12 years (Table II). Similar findings have been observed in many studies. McKinnon et al. (2007) reported a prevalence of stuttering of ∼ 0.6% in grade 1 of primary school, with progressive decline to 0.07% in grade 5. It should be noted that the total prevalence of stuttering reported in the study of McKinnon et al. was 0.33 in primary school children—almost a third less than our finding—which in turn may explain the discrepancy in prevalence observed in the two studies at different grade levels. It is generally accepted that stuttering often starts by age 2–4 years, coinciding with language development, particularly the use of 2–3 word phrases (Reilly, Onslow, Packman, Wake, Bavin, Prior, et al., 2009). Longitudinal studies on stuttering show a spontaneous recovery rate of 65–80% up to the teenage years, but decreasing significantly if the problem persists after 16 years (Dworzynski, Remington, Rijksdijk, Howell, & Plomin, 2007). This phenomenon is most likely the reason for the lower prevalence observed with progressing age. Sex has been reported as one of the factors linked to stuttering. Studies have pointed out that the disorder affects males more than females, especially in adults (Yairi & Ambrose, 2013). The sex (male/female) differential is smaller in pre-school children, ∼ 2/1 or less, and gradually increases with age to become 3/1 or even 5/1 in adults (Craig et al., 2002; Yairi & Ambrose, 1999). The current study showed that the prevalence of stuttering was 1.32-times higher in males than females. Although statistically insignificant, the trend is inclined towards male predominance. The observed stuttering sex ratio in the current study is less than the doubled or tripled male risk reported in other studies (Craig et al., 2002; Yairi & Ambrose, 1999). One study carried out in Iran, a country with comparable social and cultural characteristics to Egypt, revealed a sex ratio for stuttering of 1.29 in elementary school (Mohamadi et al., 2008). This finding is almost identical to our result. The apparent difference between our results and the Iranian study, compared to other studies in developed countries, may suggest a true racial effect or a social factor that hinders female education, which then leads to under-representation
Downloaded by [University of Birmingham] at 13:46 10 November 2015
of the female population in school samples. Such a situation was encountered in our study where females represented only one third of the sample. Another aspect revealed in the current study is the relation of the dominant hand to stuttering. Stuttering was 7-times more prevalent in left-handed than right-handed students (Table II). Individual hand preference has not been extensively studied in developmental stuttering, despite the long-standing hypothesis that developmental stuttering may be associated with atypical cerebral laterality. Atypical hand preference may be a marker of atypical cerebral laterality or atypical brain dominance. Left-handed individuals have been reported to show more stuttering (Bryngelson & Clark, 1993) as well as greater tendency to chronic stuttering (Brosch, Haege, Kalehne, & Johannsen, 1999). Stuttering is often perceived as a stigmatizing disorder for both the child and the family. Studies have shown that most families are affected by their child’s stuttering. The most frequently reported reactions are worry/anxiety/concern, uncertainty about what to do and frustration (Langevin, Packman, & Onslow, 2010). The current study showed that almost one quarter of families of affected children expressed anxiety regarding their child’s stuttering (Table III). Whether or not this result is an under-estimate, as many parents may deny any reaction towards the disorder, it points to a considerable effect on the families of affected children. Growing evidence supports a link between genetics and stuttering (Ambrose, Yairi, & Cox, 1993; Yairi, Ambrose, & Cox, 1996), and it has been the focus of research since the 1930s. There are many approaches to studying the genetic contribution to stuttering, including twin studies, family aggregation, and recent biological genetic studies. Recent twin studies confirm a strong genetic contribution to stuttering. In the Netherlands, van Beijsterveldt, Felsenfeld, and Boomsma (2010) looked at 10,500 5-year-old Dutch twin pairs. In this study, concordance for probable stuttering across sexes was 57% in monozygotic vs 31% for dizygotic pairs. In Japan, Ooki (2005) investigated a similar size sample of 1896 twin pairs. Concordance for stuttering in monozygotic pairs was 52%, but only 12% in dizygotic pairs. A recent Australian study concluded that ∼ 70% of the variance in liability for stuttering was attributable to additive genetic effects, the remainder being due to environmental effects (Felsenfeld, Kirk, Zhu, Statham, Neale, & Martin, 2000). Although the current study is not a twin study, it showed the presence of stuttering in five out of eight identical twin pairs, representing 62%, a figure close to that published in the aforementioned literature. One well-known family aggregation study carried out in the 1960s showed that the incidence of stuttering among first-degree relatives was 13.65%, substantially above the expected 5% for the general
Stuttering in school children in Egypt 371
population, with male relatives having a risk more than double that of females (Kay, 1964). A subsequent study used a sample drawn from the families of 69 pre-school children recruited soon after stuttering onset, before natural recovery had taken place. This study reported a family history of stuttering in more than two thirds of the sample, especially among first- and second-degree relatives, and confirmed the differential distribution of stuttering among male relatives (Ambrose et al., 1993). In 2005, Yairi and Ambrose reported a positive family history of stuttering for 69% of 123 families studied. Compared with the above-mentioned studies, the current study revealed a lower percentage with positive family history (28%). However, it showed male predominance in the relatives affected, in accordance with the studies of Kay and Ambrose et al. The discrepancy between the family history of 28% found in our study and the 70% reported in other studies can be explained in two ways: families may deny any family history of stuttering as they may perceive this disorder as stigmatizing, especially in our Middle Eastern culture; or they may have just replied according to their belief as they were unaware of the genetic background of the disorder, thus yielding an under-estimated proportion. One study conducted in Egypt with 100 parents of stuttering children revealed that only 8% of them thought stuttering had a genetic origin and ∼ 40% of them felt disappointed or did not accept their child’s disorder (Safwat & Sheikhany, 2014), which supports the above explanation. The current study highlighted the underresearched problem of stuttering in school children in Cairo. The finding of a prevalence rate of 1.03% is similar to that observed in other areas in the world. The prevalence of stuttering was observed to decrease with advancing age. Stuttering was more common among left-handed children and trended higher among males, although this latter result was not significant. The findings show that stuttering affects families, with evidence of hereditary origin.
Acknowledgement The authors express their great thanks to the administrative authorities of selected schools for their support in carrying out this research as well to children and their families who participated in the study. This research was approved by the Ethical research Committee of Ain shams Faculty of Medicine and was not funded by any national or international agency. Declaration of Interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.
372 M. Abouel Ella et al.
Downloaded by [University of Birmingham] at 13:46 10 November 2015
References Ambrose, N. G., Yairi, E., & Cox, N. (1993). Genetic aspects of early childhood stuttering. Journal of Speech, Language, and Hearing Research, 36, 701–706. American Speech-Language-Hearing Associations (ASHA). (1999). Terminology pertaining to fluency and fluency disorders: guidelines ASHA; supplement No. 19, 41-2,29–36. Au-Yeung, J., Howell, P., Charles, N., & Sackin, S. (2000). UCL survey of bilingualism and stuttering. In Bosshardt, H. -G. G., Yaruss, S., Peters, H., (Eds.), Proceedings of the 3rd World Congress on Fluency Disorders (p. 129–132). Nijmegen: Nijmegen University Press. Boyle, C., Boulet, S., Schieve, L., Cohen, R., Blumberg, S., Yeargin-Allsopp, M., et al. (2001). Trends in the Prevalence of Developmental Disabilities in US Children, 1997–2008. Pediatrics, 34, 385–395. Brosch, S., Haege, A., Kalehne, P., & Johannsen, H. S. (1999). Stuttering children and the probability of remission—the role of cerebral dominance and speech production. International Journal of Pediatric Otorhinolaryngolology, 47, 71–76. Bryngelson, B., & Clark, T. (1993). Left-handedness and stuttering. Journal of Heredity, 24, 387–390. Craig, A., Hancock, K., Tran, V., Craig, M., & Peters, K. (2002). Epidemiology of stuttering in the community across the entire life span. Journal of Speech, Language, and Hearing Research, 45, 1097–1105. Dworzynski, K., Remington, A., Rijksdijk, F., Howell, P., & Plomin, R. (2007). Genetic etiology in cases of recovered and persistent stuttering in an unselected longitudinal sample of young twins. American Journal of Speech-Language Pathology, 16, 167–178. Felsenfeld, S. (2002). Finding susceptibility genes for developmental disorders of speech: The long and winding road. Journal of Communication Disorders, 35, 329–345. Felsenfeld, S., Kirk, K. M., Zhu, G., Statham, D. J., Neale, M. C., & Martin, N. G. (2000). A study of the genetic and environmental etiology of stuttering in a selected twin sample. Behavior Genetics, 30, 359–366. Harasty, J., & Reed, V. (1994). The prevalence of speech and language impairment in two Sydney metropolitanschools: A summary and critical review. Australian Journal of Human Communication Disorders, 22, 63–80. Karbasi, S. A., Fallah, R., & Golestan, M. (2011). The prevalence of speech disorder in primary school students in Yazd-Iran. Acta Medica Iranica, 49, 33–37. Kay, D. (1964). The genetics of stuttering. In G., Andrews, & M., Harris, (Eds.), The Syndrome of Stuttering (pp 132–143). London: The Spastic Society Medical Education and Information Unit. Keating, D., Turrell, G., & Ozanne, A. (2001). Childhood speech disorders: Reported prevalence, comorbidity and socioeconomic profile. Journal of Paediatrics and Child Health, 37, 431–436. Klompas, M., & Ross, E. (2004). Life experiences of people who stutter, and the perceived impact of stuttering on quality of life: Personal accounts of South African individuals. Journal of Fluency Disorders, 29, 275–305. Koedoot, C., Bouwmans, C., Franken, M., & Stolk, E. (2011). Quality of life in adults who stutter. Journal of Communication Disorders, 44, 429–443. Langevin, M., Packman, A., & Onslow, M. (2009). Peer responses to stuttering in the preschool setting. American Journal of Speech Language Pathology, 18, 264–276. Langevin, M., Packman, A., & Onslow, M. (2010). Parent perceptions of the impact of stuttering on their preschoolers and themselves. Journal of Communication Disorders, 43, 407–423. McAllister, J., Collier, J., & Shepstone, L. (2012). The impact of adolescent stuttering on educational and employment outcomes: Evidence from a birth cohort study. Journal of Fluency Disorders, 37, 106–121.
McAllister, J., Collier, J., & Shepstone, L. (2013). The impact of adolescent stuttering and other speech problems on psychological well-being in adulthood: evidence from a birth cohort study. International Journal of Language & Communication Disorders, 48, 458–468. McKinnon, D., McLeod, S., & Reilly, S. (2007). The Prevalence of Stuttering, Voice, and Speech-Sound Disorders in Primary School Students in Australia. Language, Speech, and Hearing Services in Schools, 38, 5–15. McLeod, S., & Harrison, L. (2009). Epidemiology of speech and language impairment in a nationally representative sample of 4- to 5-year-old children. Journal of Speech, Language, and Hearing Research, 52, 113–129. Messenger, M., Onslow, M., Packman, A., & Menzies, R. (2004). Social anxiety in stuttering: Measuring negative social expectancies. Journal of Fluency Disorders, 29, 201–212. Mohamadi, H., Nilipour, R., & Yadegari, F. (2008). Stuttering prevalence among Kurdish-Farsi students; Effects of the two languages similarities. Iranian Rehabilitation Journal, 6, 83–88. O’Brian, S., Jones, M., Packman, A., Menzies, R., & Onslow, M. (2011). Stuttering severity and educational attainment. Journal of Fluency Disorders, 36, 86–92. Okalidou, A., & Kampanaros, M. (2001). Teacher perceptions of communication impairment at screening stage in preschool children living in Patras, Greece. International Journal of Language & Communication Disorders, 36, 489–502. Okasha, A., Bishry, Z., Kamel, M., & Hassan, A. H. (1974). Psychosocial study of stammering in Egyptian children. British Journal of Psychiatry, 124, 534–535. Ooki, S. (2005). Genetic and environmental influences on stuttering and tics in Japanese children. Twin Research and Human Genetics, 8, 69–75. Peters, T. J., & Guitar, B. (1991). Stuttering an integrated approach to its nature and treatment. Baltimore, MD: Williams & Wilkins. Proctor, A., Yairi, E., & Duff, M. (2008). Prevalence of stuttering in African American preschool children. Journal of Speech, Language, and Hearing Research, 50, 1465–1474. Reilly, S., Onslow, M., Packman, A., Cini, E., Conway, L., Ukoumunne, O. C., et al. (2013). Natural History of Stuttering to 4 Years of Age: A Prospective Community – Based Study. Pediatrics, 132, 460–467. Reilly, S., Onslow, M., Packman, A., Wake, M., Bavin, E. L., Prior, M., et al. (2009). Predicting Stuttering Onset by the Age of 3 Years: A Prospective, Community Cohort Study. Pediatrics, 123, 270–277. Safwat, R. F., & Sheikhany, A. (2014). Parental attitudes and knowledge of stuttering. The Egyptian Journal of Otolaryngology, 30, 151–156. Van Beijsterveldt, C. E. M., Felsenfeld, S., & Boomsma, D. I. (2010). Bivariate genetic analysis of stuttering and non fluency in a large sample of 5-year-old twins. Journal of Speech, Language, and Hearing Research, 53, 609–619. Van Borsel, J., Moeyaert, J., Mostaert, C., Rosseel, R., Van Loo, E., & Van Renterghem, T. (2006). Prevalence of stuttering in regular and special school populations in Belgium based on teacher perceptions. Folia Phoniatrica et Logopaedica, 58, 289–302. Yairi, E., & Ambrose, N. G. (1999). Early childhood stuttering I: persistency and recovery Journal of Speech, Language, and Hearing Research, 42,1097–1112. Yairi, E., & Ambrose, N. G. (2005). Early Childhood Stuttering. Austin, TX: Pro Ed. Yairi, E., & Ambrose, N. G. (2013). Epidemiology of Stuttering: 21st Century Advances. Journal of Fluency Disorders, 38, 66–87. Yairi, E., Ambrose, N. G., & Cox, N. (1996). Genetics of stuttering: A critical review. Journal of Speech, Language, and Hearing Research, 39,771–784.
