Clin Rheumatol DOI 10.1007/s10067-014-2693-0

ORIGINAL ARTICLE

A prospective study of perceived injustice in whiplash victims and its relationship to recovery Robert Ferrari

Received: 8 May 2014 / Revised: 10 May 2014 / Accepted: 23 May 2014 # Clinical Rheumatology 2014

Abstract The objectives of this paper are to to measure levels of perceived injustice in whiplash victims and determine the relationship to recovery at 6-month post-injury. Consecutive acute whiplash patients completed the Injustice Experience Questionnaire, at presentation, and also 3- and 6-month postinjury. At each of these two follow-up points, participants were examined for recovery. Of an initial 134 participants, 130 participants were followed up at 3 months and 124 at 6 months. At the 3-month follow-up, 62 % (80/130) of participants reported recovery from their injuries. At 6 months, 80 % (99/124) reported recovery. The initial Injustice Experience Questionnaire score was low, with a mean score of 6.0± 1.0 (range 5–10) out of a maximum of 48. The mean score at 3-month follow-up had increased in the cohort to 7.4±1.6 (range 5–11). At 6-month post-injury, the mean of the Injustice Experience Questionnaire score for the cohort who still reported lack of recovery (25/124 participants) was 15.0±6.0 (range 5–31), while that for the recovered group remained low at 8.2±3.9 (range 5–11). In the primary care setting, a significant proportion of whiplash patients who have not recovered by 3-month post-injury subsequently develop higher levels of perceived injustice by 6-month post-injury. The development of high levels of perceived injustice at 6-month post-injury appears to follow the development of chronic pain and a lack of recovery at 3 months and, at that point, becomes a risk factor for lack of recovery thereafter.

Keywords Chronic pain . Injustice . Pain . Recovery . Whiplash injury

R. Ferrari (*) Department of Medicine and Department of Rheumatic Diseases, University of Alberta, 13-103 Clinical Sciences Building, Edmonton, Alberta T6G 2P4, Canada e-mail: [email protected]

Introduction It has been demonstrated, in the primary care setting, that a significant proportion of patients will recover from whiplash injury by 3-month post-injury [1–5]. Coping style and expectation have been shown to predict this recovery in both the primary care setting and in population-based studies [2, 6–8]. What happens to the cohort of non-recovered participants after 3 months is less well documented, and the reasons why some recover gradually versus not at all after this point have also not been well studied. Clinicians generally regard a patient not recovered from whiplash injury by 3–6-month post-injury as a patient with a high likelihood of chronic pain for years thereafter, unresponsive to treatment interventions. Certainly, a recent study suggests that those who have chronic whiplash (i.e., lack of recovery 3–6-month post-injury) are unlikely to respond even to intensive rehabilitation efforts [9]. The mechanism of the transition from chronic pain and the resistance to interventions is not well understood. One possibility is perceived injustice. Perceived injustice is operationally defined as a multidimensional construct, composed of elements that assess the severity of loss, irreparability of loss, blame, and sense of unfairness [10–13]. The degree of perceived injustice has been shown in chronic pain sufferers (including cohorts involved in motor vehicle collisions) to be associated with higher pain severity, depression, catastrophizing, fear of movement, self-reported disability, protective pain behaviors, less progress in rehabilitation, and lower probability of return to work [11–13]. The higher the level of perceived injustice, the lower the likelihood of subsequent response to rehabilitation. Scott et al. [14] studied 103 whiplash-injured participants, some 2–6 months after injury; none of whom had recovered by the time of the study initiation. This was a group selected not from consecutively presenting primary care patients, but rather from rehabilitation clinics. Nevertheless, measuring perceived injustice via the

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Injustice Experience Questionnaire (IEQ) at the outset of the study, and then re-examining participants after the completion of a 7-week program and 1 year later, Scott et al. showed that IEQ scores significantly discriminated individuals who returned and did not return to work at 1 year. An IEQ score of 19 (out of a maximum of 48) optimally identified participants in terms of follow-up employment status. IEQ scores at the end of treatment also discriminated individuals with high and low pain severity ratings and narcotic use status at the 1year follow-up. The question is when and why this higher level of perceived injustice develops. Is it present early after the injury event (i.e., in the first few weeks), or does it develop months later? Do participants who report recovery at 3- and 6-month post-whiplash injury have different perceptions of injustice than those who do not report recovery at these time points? To date, there have been no studies that have prospectively evaluated perceived injustice among consecutively selected acute whiplash victims in the primary care setting. The purposes of the current study were to prospectively evaluate perceived injustice in a cohort of primary care acute whiplash injury participants and determine the relationship between recovery and perceived injustice.

interior of a car, truck, sports/utility vehicle, or van in a collision (any of rear, frontal, or side impact); had no loss of consciousness; were 18 years of age or over; and presented within 14 days of their collision. Patients were excluded if they were told they had a fracture or neurological injury (i.e., grade 3 or grade 4 WAD), had objective neurologic signs on examination (loss of reflexes, sensory loss—i.e., grade 3 WAD), previous whiplash injury or a recollection of prior spinal pain requiring treatment, no fixed address or current contact information, were unable to communicate in English, had non-traumatic pain, were injured in a non-motor vehicle event, or were admitted to hospital. As part of the objective was a determination of the proportion of recovery at 3 and 6 months, participants who had additional collisions with reported injury during this period of follow-up were also excluded. Measurements

The author gathered data on these participants referred over a 5-month period, the measurements being conducted at the initial and follow-up consultation as part of the routine measures provided to all patients (i.e., as part of usual assessment).

The IEQ was used, as described by Sullivan et al. [9], to measure injury-related perceptions of injustice. Participants were asked to rate the frequency with which they experienced each of 12 pain-related thoughts on a 5-point scale, ranging from 0 (never) to 4 (all the time). Examples of items include “Most people don’t understand how severe my condition is,” “My life will never be the same,” “I am suffering because of someone else’s negligence,” and “It all seems so unfair.” The maximum score (maximal perceived injustice) is 48 and the minimum is 0. The scale can be further divided and scored along two factors: blame/unfairness and severity/irreparability of loss. Subjects were asked to return for 3- and 6-month assessment even if improved or recovered. Because the author was also involved in the care of these participants for other medical problems, the author also used these opportunities to capture further data on recovery and perceived injustice near the 3and 6-month follow-up or enlisted the help of the primary care physician to obtain this data. At 3- and 6-month post-injury, recovery was assessed with the question “ Do you feel you have recovered from your injuries?” with responses of “yes,” “no,” or “not sure.” This has been shown to be as useful as completing a disability questionnaire and similar measures of recovery [15]. Further follow-up of the participants who failed to report recovery at 6 months was undertaken in person or by phone, using the above question. This final follow-up took place 9–13-month post-injury.

Inclusion and exclusion criteria

Data analysis

Prospective participants were further assessed for inclusion and exclusion criteria at the time of initial interview. Subjects were examined to determine their WAD grade [7]. WAD grade 1 or 2 patients were included if they were seated within the

The author had no knowledge of IEQ scores until completion of the 6-month follow-up, as data was kept in a sealed envelope with the patient’s name. Then, after an anonymization process (each patient given a number to replace their name),

Methods Participants The author recruited a cohort of consecutive whiplash-injured patients presenting within 14 days of their collision to a single walk-in primary care center. Patients with a motor vehicle collision and suspected whiplash-associated disorder (WAD) were routinely referred from general practitioners at the clinic, directly to the author, who was acting as a specialist consultant within that clinic. The specialist was an internist with an interest in rheumatology and chronic pain. It was the practice during the time of this consultant’s presence at the clinic to refer all acute whiplash patients to the consultant. Data collection

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data entry took place. Initially, all data records were reviewed in order to ascertain if any data issues, such as missing data, outliers, or out of range values, existed within the data set. The mean age, sex distribution, and mean scores of the IEQ assessments were calculated at the initial assessment, 3month follow-up, and 6-month follow-up. The proportion of participants who recovered were also calculated at 3 and 6 months. The mean IEQ scores were calculated for the recovered and non-recovered groups at each follow-up time point. Inferential statistics were then used to determine whether participants in the two groups (recovered and non-recovered) had significantly different IEQ scores. This was done univariately using t tests, after adjusting for potential confounders (sex and age) using preplanned analysis of covariance (ANCOVA) if needed. A 0.05 alpha level was used to judge statistical significance. All analyses were conducted using IBM SPSS Statistics for Macintosh version 20 (Chicago, IL). Sample size calculation From previous studies of chronic pain participants, the standard deviation of the IEQ has been approximately 12 [8–11]. Using this value, the author calculated that at least 110 participants would be required to provide an 80 % power to detect a difference of 6 in the group means between recovered and non-recovered participants. The author thus aimed for a sample size of at least 110 participants total. Ethics Ethical clearance was gained from the Alberta Health Ethics Research Board.

Results Data cleaning All participants who had completed the IEQ had done so completely. Data for recovered participants at 6-month follow-up was more difficult to obtain at exactly 6 months, as these patients were captured only when they had returned to the clinic for another reason. Thus, the timing of the range of follow-up varied from 22 to 28 weeks (i.e., approximately 5– 7 months). All participants were, at the time of the study, in a system of new legislation that places a cap on compensation for whiplash grades 1 and 2, of $4000, with a standardized diagnostic treatment protocol applied to each subject. This system has been described elsewhere [16]. All participants had filed a

claim with an insurance company to receive treatment benefits. Three participants had experienced their collisions in the course of work, and thus were covered (in terms of treatment) by the provincial Workers’ Compensation Board. Initially, a total of 161 participants were evaluated. From these, 27 were excluded (9 due to previous history, 2 due to loss of consciousness, 6 due to lack of ability to communicate in English, 5 due to a new collision or injury event in the period of the study, 2 due to non-motor vehicle collision injuries, 2 due to grade 3 WAD, and 1 due to having been admitted to hospital). Thus, 134 participants formed the cohort for the study.

Descriptive statistics A total of four participants were lost to follow-up at 3 months, and an additional ten participants were lost to follow-up at 6 months. A total of 130 participants were thus followed up at 3 months and 124 at 6 months. All those lost to follow-up at 6 months had reported recovery at 3 months, but since there was no additional data at 6 months concerning their IEQ scores, they were not included further in the analysis at 6 months. At 3-month follow-up, 62 % (80/130) of participants reported recovery from their injuries. At 6 months, 80 % (99/124) reported recovery from their injuries. None of the participants went from recovered to non-recovered status over the period of this study. All but four patients were grade 2 WAD. As a result, the four grade 1 WAD subjects were included in the group of WAD 2 for analysis purposes. Table 1 reveals the mean age of participants, sex distribution, and mean IEQ scores for the groups at the outset, at 3 and at 6 months. The initial IEQ scores were low in the cohort, with a mean score of 6.0±1.0 (range 5–10). The mean score at 3-month follow-up had increased in the cohort to 7.4±1.6 (range 5–11), but this difference from the initial assessment was not statistically significant (P>0.05). By 6-month postinjury, the mean IEQ score had increased to 11.0±6.0 (range 5–31), and this difference was statistically significant. Graph 1 shows the mean IEQ scores for the groups who had reported recovery or non-recovery at 3 and 6 months. As can be seen, at 3 months, there was no difference in the mean scores between recovered and non-recovered participants. At 6-month post-injury, however, the mean of the IEQ score for the cohort who still reported lack of recovery (25/124 participants) was 15.0±5.6 (range 10–31), while that for the group who had recovered remained low 8.2±1.2 (range 5–12). This difference was statistically significant. ANCOVA revealed no effect of age and sex on these crude means. At follow-up, 9–13-month post-injury, none of the 25

Clin Rheumatol Table 1 Patient characteristics and Injustice Experience Questionnaire means at the initial evaluation and at 3- and 6-month post-injury At outset (n=134) At 3 months (n=130) Mean (standard deviation) or percent

At 6 months (n=124)

Sex (% female) Age (years) Injustice Experience Questionnaire total Injustice Experience Questionnaire blame/unfairness subscale

54.5 36.6 (13.5) 6.0 (1.0) 4.3 (0.9)

53.8 37.0 (13.5) 7.4 (1.6) 5.2 (1.5)

54.8 37.1 (13.7) 11.0* (6.0) 5.8* (2.0)

Injustice Experience Questionnaire severity/irreparability subscale

1.7 (0.5)

2.3 (0.7)

5.2* (4.4)

*Statistically significant at P

A prospective study of perceived injustice in whiplash victims and its relationship to recovery.

The objectives of this paper are to to measure levels of perceived injustice in whiplash victims and determine the relationship to recovery at 6-month...
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