RESEARCH ARTICLE
Validation of the Chinese Version of the Quality of Nursing Work Life Scale Xia Fu1, Jiajia Xu2, Li Song1, Hua Li3, Jing Wang4, Xiaohua Wu3, Yani Hu3, Lijun Wei3, Lingling Gao5, Qiyi Wang6, Zhanyi Lin7*, Huigen Huang3* 1 Department of Nephrology, Guangdong General Hospital and Guangdong Academy of Medical Sciences, Guangzhou, China, 2 Cardiovascular Department, Gaomi People’s Hospital, Gaomi, China, 3 Nursing Department, Guangdong General Hospital and Guangdong Academy of Medical Sciences, Guangzhou, China, 4 School of Nursing, University of Texas Health Science Center at Houston, Houston, Texas, United States of America, 5 School of Nursing, Sun Yat-sen University, Guangzhou, China, 6 Digestive Department, Guangdong General Hospital and Guangdong Academy of Medical Sciences, Guangzhou, China, 7 Institute of Geriatric Medicine, Guangdong General Hospital and Guangdong Academy of Medical Sciences, Guangzhou, China * [email protected] (HH); [email protected] (ZL)
OPEN ACCESS Citation: Fu X, Xu J, Song L, Li H, Wang J, Wu X, et al. (2015) Validation of the Chinese Version of the Quality of Nursing Work Life Scale. PLoS ONE 10(5): e0121150. doi:10.1371/journal.pone.0121150 Academic Editor: Sari Helena Räisänen, Kuopio University Hospital, FINLAND Received: July 18, 2014 Accepted: February 6, 2015 Published: May 7, 2015 Copyright: © 2015 Fu et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability Statement: All relevant data are within the paper. Funding: The study was supported by Guangdong Provincial Scientific Planning Project (No. 2010B031900031) and the National Clinical Key Specialty Construction Preparatory Projects. The work by Wang was also supported, in part, by the Robert Wood Johnson Foundation Nurse Faculty Scholars Program. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Abstract Quality of Nursing Work Life (QNWL) serves as a predictor of a nurse’s intent to leave and hospital nurse turnover. However, QNWL measurement tools that have been validated for use in China are lacking. The present study evaluated the construct validity of the QNWL scale in China. A cross-sectional study was conducted conveniently from June 2012 to January 2013 at five hospitals in Guangzhou, which employ 1938 nurses. The participants were asked to complete the QNWL scale and the World Health Organization Quality of Life abbreviated version (WHOQOL-BREF). A total of 1922 nurses provided the final data used for analyses. Sixty-five nurses from the first investigated division were re-measured two weeks later to assess the test-retest reliability of the scale. The internal consistency reliability of the QNWL scale was assessed using Cronbach’s α. Test-retest reliability was assessed using the intra-class correlation coefficient (ICC). Criterion-relation validity was assessed using the correlation of the total scores of the QNWL and the WHOQOL-BREF. Construct validity was assessed with the following indices: χ2 statistics and degrees of freedom; relative mean square error of approximation (RMSEA); the Akaike information criterion (AIC); the consistent Akaike information criterion (CAIC); the goodness-of-fit index (GFI); the adjusted goodness of fit index; and the comparative fit index (CFI). The findings demonstrated high internal consistency (Cronbach’s α = 0.912) and test-retest reliability (interclass correlation coefficient = 0.74) for the QNWL scale. The chi-square test (χ2 = 13879.60, df [degree of freedom] = 813 P = 0.0001) was significant. The RMSEA value was 0.091, and AIC = 1806.00, CAIC = 7730.69, CFI = 0.93, and GFI = 0.74. The correlation coefficient between the QNWL total scores and the WHOQOL-BREF total scores was 0.605 (p 0.55 for each subscale [17]. A translation and back-translation process was employed in the pilot study prior to applying the questionnaire in China. Two experts in the same area of study, who spoke satisfactory English but were not familiar with the scale, were invited to translate the English version of the scale into Chinese. After comparison and discussion, a preliminary draft was obtained. The translation quality of the draft was evaluated by two English teachers and then was discussed by six professionals who are experienced in scale design from the fields of public health, clinical nursing, clinical care and psychology, to generate a revised version (S1 Table). Thirty nurses from some of the divisions of the hospital where the investigators work were selected randomly for retesting, and a final draft was obtained after modifications. The WHOQOL-BREF. The WHOQOL-BREF has 26 items; it is a 5-point scale used to assess quality of life. The WHOQOL-BREF consists of four subscales (physiology domain, psychology domain, social relationship domain, and environmental domain), with good reliability and validity. The Chinese version of the WHOQOL-BREF was translated and modified by Fang Jiqian, and this questionnaire has been widely used in China with strong reliability and validity. In the present study, Cronbach’s α for the WHOQOL-BREF was 0.83.
Procedure and ethical considerations We explained the study purpose and procedures to the participating nurses. Voluntary participation and data confidentiality were clarified. We performed a pilot study with 30 nurses to test the logistics of the study, and we did not find any problems from the nurses in understanding the QNWL items. We also conducted several training sessions for the research assistant to ensure that the data collection process was consistently performed for all nurse participants.
PLOS ONE | DOI:10.1371/journal.pone.0121150 May 7, 2015
3 / 12
Validation of the Chinese Version of the QNWLS
Data collection and analysis After the research assistant received informed consent, the participants were asked to complete the demographic scale, the QNWL and the WHOQOL-BREF and then to return the completed scales to the research assistant. Scale completion required approximately 10–13 minutes. A demographic scale was used to summarize demographic characteristics of the study sample. Cronbach’s α was used to assess the internal consistency reliability of the QNWL scale. The intra-class correlation coefficient (ICC) was used to assess the test-retest reliability, and an ICC greater than 0.70 indicated acceptable test-retest reliability over 2 weeks [18, 19]. The correlation between the total scores of the QNWL and WHOQOL-BREF was used to assess the criterion-relation validity of the QNWL scale, and a correlation coefficient between 0.4 and 0.8 was satisfactory [20]. Pearson’s correlation coefficients of each item of the QNWL scale with the four subscales and total score were used to assess the content validity of the scale. A higher correlation coefficient indicated better content validity [20]. The normal distribution of the total scores on the QNWL and WHOQOL-BREF was analyzed. When the scores did not satisfied a normal distribution, the Mann-Whitney test was used to compare between the groups, and the Kruskal-Wallis test was used among groups to assess the discrimination validity of the scale for different populations. A factor model was constructed according to the theoretical structure of the QNWL. Confirmatory factor analysis was performed, and the theoretical factor model was fit with actual data. The factor loading values indicated that the items had significant loadings on the four subscales. Factor loads greater than 0.3 indicated subordinate relationships and a strong correlation between the item and the corresponding subscale [21], as well as the existence of the theoretical structure of the QNWL. The construct validity of the scale was assessed using the following indices: χ2 statistics and degrees of freedom for the overall fit of the model to data, the adjusted goodness of fit index, (AGFI), the relative mean square error of approximation (RMSEA), the standardized root mean square residual (SRMR), the Akaike information criterion (AIC), the consistent Akaike information criterion (CAIC), the comparative fit index (CFI), the normed fit index (NFI), the non-normed fit index (NNFI), and the incremental fit index (IFI). Statistical analysis was performed with SPSS software, version 16.0 (Chicago, IL, USA), and LISREL software, version 8.7 (Lincolnwood, IL, USA).
Results Sample characteristics A total of 1938 surveys were administered to nurses in the selected hospitals using a convenience sample. Of the 1922 nurses who completed questionnaires, we excluded those who did not provide complete data for the key outcome variables, including the QNWL and the WHOQOL-BREF. In total, 1922 nurses provided the final data used for the analyses. The overall response rate was 99.17% (n = 1922). The typical characteristics of the 1922 were 96.1% female (n = 1847), average age of 30.0±6.93 (ranging 19–55) years old, 54.4% (n = 1045) married and an average working time of 9.0±7.7 (ranging 0.5–38) years. The typical respondents were 82.7% staff nurses (n = 1590), 13.7% team leaders (n = 263) and 3.6% assistant nurses (n = 69). Overall, 38.3% (n = 736) of the 1922 respondents were working full time in internal medicine, 25.2% (n = 485) in surgery, 22.1% (n = 426) in emergency and ICUs, and 3.7% (n = 71) in obstetrics and gynecology (Table 1).
PLOS ONE | DOI:10.1371/journal.pone.0121150 May 7, 2015
4 / 12
Validation of the Chinese Version of the QNWLS
Table 1. The sociodemographic characteristics of the study sample (n = 1922). Characteristic
Means ± SD
Age
30.0±6.93
Working time
9.0±7.7
Characteristic
n (%) Sex
Female
1847 (96.1%)
Male
75 (3.9%) Marital status
Married
1045 (54.4%)
Single
849 (44.2%)
Other
28 (1.4%) Status
Junior nurses
846 (44.0%)
Senior nurses
685 (35.6%)
Nurses in charge
391 (20.3%) Nursing position
Staff nurses
1590 (82.7%)
Team leader
263 (13.7%)
Assistant nurses
69 (3.6%) Working department
Internal medicine
736 (38.3%)
Surgery
485 (25.2%)
Emergency and ICU
426 (22.1%)
Pediatrics
106 (5.5%)
Obstetrics and gynecology
71 (3.7%)
Others
98 (5.2%) Personal income (monthly)
Validation of the Chinese Version of the Quality of Nursing Work Life Scale Xia Fu1, Jiajia Xu2, Li Song1, Hua Li3, Jing Wang4, Xiaohua Wu3, Yani Hu3, Lijun Wei3, Lingling Gao5, Qiyi Wang6, Zhanyi Lin7*, Huigen Huang3* 1 Department of Nephrology, Guangdong General Hospital and Guangdong Academy of Medical Sciences, Guangzhou, China, 2 Cardiovascular Department, Gaomi People’s Hospital, Gaomi, China, 3 Nursing Department, Guangdong General Hospital and Guangdong Academy of Medical Sciences, Guangzhou, China, 4 School of Nursing, University of Texas Health Science Center at Houston, Houston, Texas, United States of America, 5 School of Nursing, Sun Yat-sen University, Guangzhou, China, 6 Digestive Department, Guangdong General Hospital and Guangdong Academy of Medical Sciences, Guangzhou, China, 7 Institute of Geriatric Medicine, Guangdong General Hospital and Guangdong Academy of Medical Sciences, Guangzhou, China * [email protected] (HH); [email protected] (ZL)
OPEN ACCESS Citation: Fu X, Xu J, Song L, Li H, Wang J, Wu X, et al. (2015) Validation of the Chinese Version of the Quality of Nursing Work Life Scale. PLoS ONE 10(5): e0121150. doi:10.1371/journal.pone.0121150 Academic Editor: Sari Helena Räisänen, Kuopio University Hospital, FINLAND Received: July 18, 2014 Accepted: February 6, 2015 Published: May 7, 2015 Copyright: © 2015 Fu et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability Statement: All relevant data are within the paper. Funding: The study was supported by Guangdong Provincial Scientific Planning Project (No. 2010B031900031) and the National Clinical Key Specialty Construction Preparatory Projects. The work by Wang was also supported, in part, by the Robert Wood Johnson Foundation Nurse Faculty Scholars Program. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Abstract Quality of Nursing Work Life (QNWL) serves as a predictor of a nurse’s intent to leave and hospital nurse turnover. However, QNWL measurement tools that have been validated for use in China are lacking. The present study evaluated the construct validity of the QNWL scale in China. A cross-sectional study was conducted conveniently from June 2012 to January 2013 at five hospitals in Guangzhou, which employ 1938 nurses. The participants were asked to complete the QNWL scale and the World Health Organization Quality of Life abbreviated version (WHOQOL-BREF). A total of 1922 nurses provided the final data used for analyses. Sixty-five nurses from the first investigated division were re-measured two weeks later to assess the test-retest reliability of the scale. The internal consistency reliability of the QNWL scale was assessed using Cronbach’s α. Test-retest reliability was assessed using the intra-class correlation coefficient (ICC). Criterion-relation validity was assessed using the correlation of the total scores of the QNWL and the WHOQOL-BREF. Construct validity was assessed with the following indices: χ2 statistics and degrees of freedom; relative mean square error of approximation (RMSEA); the Akaike information criterion (AIC); the consistent Akaike information criterion (CAIC); the goodness-of-fit index (GFI); the adjusted goodness of fit index; and the comparative fit index (CFI). The findings demonstrated high internal consistency (Cronbach’s α = 0.912) and test-retest reliability (interclass correlation coefficient = 0.74) for the QNWL scale. The chi-square test (χ2 = 13879.60, df [degree of freedom] = 813 P = 0.0001) was significant. The RMSEA value was 0.091, and AIC = 1806.00, CAIC = 7730.69, CFI = 0.93, and GFI = 0.74. The correlation coefficient between the QNWL total scores and the WHOQOL-BREF total scores was 0.605 (p 0.55 for each subscale [17]. A translation and back-translation process was employed in the pilot study prior to applying the questionnaire in China. Two experts in the same area of study, who spoke satisfactory English but were not familiar with the scale, were invited to translate the English version of the scale into Chinese. After comparison and discussion, a preliminary draft was obtained. The translation quality of the draft was evaluated by two English teachers and then was discussed by six professionals who are experienced in scale design from the fields of public health, clinical nursing, clinical care and psychology, to generate a revised version (S1 Table). Thirty nurses from some of the divisions of the hospital where the investigators work were selected randomly for retesting, and a final draft was obtained after modifications. The WHOQOL-BREF. The WHOQOL-BREF has 26 items; it is a 5-point scale used to assess quality of life. The WHOQOL-BREF consists of four subscales (physiology domain, psychology domain, social relationship domain, and environmental domain), with good reliability and validity. The Chinese version of the WHOQOL-BREF was translated and modified by Fang Jiqian, and this questionnaire has been widely used in China with strong reliability and validity. In the present study, Cronbach’s α for the WHOQOL-BREF was 0.83.
Procedure and ethical considerations We explained the study purpose and procedures to the participating nurses. Voluntary participation and data confidentiality were clarified. We performed a pilot study with 30 nurses to test the logistics of the study, and we did not find any problems from the nurses in understanding the QNWL items. We also conducted several training sessions for the research assistant to ensure that the data collection process was consistently performed for all nurse participants.
PLOS ONE | DOI:10.1371/journal.pone.0121150 May 7, 2015
3 / 12
Validation of the Chinese Version of the QNWLS
Data collection and analysis After the research assistant received informed consent, the participants were asked to complete the demographic scale, the QNWL and the WHOQOL-BREF and then to return the completed scales to the research assistant. Scale completion required approximately 10–13 minutes. A demographic scale was used to summarize demographic characteristics of the study sample. Cronbach’s α was used to assess the internal consistency reliability of the QNWL scale. The intra-class correlation coefficient (ICC) was used to assess the test-retest reliability, and an ICC greater than 0.70 indicated acceptable test-retest reliability over 2 weeks [18, 19]. The correlation between the total scores of the QNWL and WHOQOL-BREF was used to assess the criterion-relation validity of the QNWL scale, and a correlation coefficient between 0.4 and 0.8 was satisfactory [20]. Pearson’s correlation coefficients of each item of the QNWL scale with the four subscales and total score were used to assess the content validity of the scale. A higher correlation coefficient indicated better content validity [20]. The normal distribution of the total scores on the QNWL and WHOQOL-BREF was analyzed. When the scores did not satisfied a normal distribution, the Mann-Whitney test was used to compare between the groups, and the Kruskal-Wallis test was used among groups to assess the discrimination validity of the scale for different populations. A factor model was constructed according to the theoretical structure of the QNWL. Confirmatory factor analysis was performed, and the theoretical factor model was fit with actual data. The factor loading values indicated that the items had significant loadings on the four subscales. Factor loads greater than 0.3 indicated subordinate relationships and a strong correlation between the item and the corresponding subscale [21], as well as the existence of the theoretical structure of the QNWL. The construct validity of the scale was assessed using the following indices: χ2 statistics and degrees of freedom for the overall fit of the model to data, the adjusted goodness of fit index, (AGFI), the relative mean square error of approximation (RMSEA), the standardized root mean square residual (SRMR), the Akaike information criterion (AIC), the consistent Akaike information criterion (CAIC), the comparative fit index (CFI), the normed fit index (NFI), the non-normed fit index (NNFI), and the incremental fit index (IFI). Statistical analysis was performed with SPSS software, version 16.0 (Chicago, IL, USA), and LISREL software, version 8.7 (Lincolnwood, IL, USA).
Results Sample characteristics A total of 1938 surveys were administered to nurses in the selected hospitals using a convenience sample. Of the 1922 nurses who completed questionnaires, we excluded those who did not provide complete data for the key outcome variables, including the QNWL and the WHOQOL-BREF. In total, 1922 nurses provided the final data used for the analyses. The overall response rate was 99.17% (n = 1922). The typical characteristics of the 1922 were 96.1% female (n = 1847), average age of 30.0±6.93 (ranging 19–55) years old, 54.4% (n = 1045) married and an average working time of 9.0±7.7 (ranging 0.5–38) years. The typical respondents were 82.7% staff nurses (n = 1590), 13.7% team leaders (n = 263) and 3.6% assistant nurses (n = 69). Overall, 38.3% (n = 736) of the 1922 respondents were working full time in internal medicine, 25.2% (n = 485) in surgery, 22.1% (n = 426) in emergency and ICUs, and 3.7% (n = 71) in obstetrics and gynecology (Table 1).
PLOS ONE | DOI:10.1371/journal.pone.0121150 May 7, 2015
4 / 12
Validation of the Chinese Version of the QNWLS
Table 1. The sociodemographic characteristics of the study sample (n = 1922). Characteristic
Means ± SD
Age
30.0±6.93
Working time
9.0±7.7
Characteristic
n (%) Sex
Female
1847 (96.1%)
Male
75 (3.9%) Marital status
Married
1045 (54.4%)
Single
849 (44.2%)
Other
28 (1.4%) Status
Junior nurses
846 (44.0%)
Senior nurses
685 (35.6%)
Nurses in charge
391 (20.3%) Nursing position
Staff nurses
1590 (82.7%)
Team leader
263 (13.7%)
Assistant nurses
69 (3.6%) Working department
Internal medicine
736 (38.3%)
Surgery
485 (25.2%)
Emergency and ICU
426 (22.1%)
Pediatrics
106 (5.5%)
Obstetrics and gynecology
71 (3.7%)
Others
98 (5.2%) Personal income (monthly)
