Psychometric properties of the Persian version of the brief illness questionnaire in Iranian with non-specific chronic neck pain.

INTRODUCTION: The Brief Illness Perception Questionnaire (BIPQ) is an instrument for assessing the illness perception. Illness perception varies between individuals based on their health status. There is no study that assess the psychometric properties of the Persian version of BIPQ in neck pain patients. The goal of this study was to evaluate the reliability, construct validity, and exploratory factor analysis of the Persian BIPQ in individuals with non-specific chronic neck pain. METHODS: This is a cross-sectional study in which 123 individuals with non-specific chronic neck pain participated. 60 participants examined after 7 days for testing reliability. Reliability was assessed by intra-class correlation coefficient, standard error of measurement, and minimal detectable change. For assessing construct validity and item-total correlation, correlation tests were used. Also, exploratory factor analysis was done to assess the factor structure of the BIPQ. RESULTS: Exploratory factor analysis' results showed that there were 2 factors with Eigenvalues >1. Factor 1 included "identity", "consequence", "timeline", and "emotional response". Factor 2 consisted of "coherence" and "treatment control". The intra-class correlation coefficient and the cronbach's alpha for the total score was 0.8 and 0.86 respectively. Results of correlation tests showed an acceptable construct validity except with SF-12 mental component. Item-total correlation tests demonstrated that the correlations were above 0.3 for all subscales except for "treatment control" and "coherence". CONCLUSION: BIPQ has an acceptable properties to assess illness perception in individuals with non-specific chronic neck pain. The results of exploratory factor analysis and item-total correlation confirmed that 2-subscale version is more acceptable.

Reliability of postural control during double-leg standing in subjects with nonspecific chronic low back pain: Dual-task paradigm and manipulated visual and somatosensory inputs.

BACKGROUND: The aim of this study is to evaluate the test-retest reliability of the Center of Pressure (COP) parameters in quiet double-leg standing in subjects with Non-Specific Chronic Low Back Pain (NSCLBP) during dual taking associated with manipulated visual and somatosensory inputs. MATERIALS AND METHODS: In this observational cross-sectional study, the static balance of thirty NSCLBP patients were assessed during a double-leg stance by using the force platform. Subjects were accosted by manipulated somatosensory and visual inputs during dual taking in eight different conditions (with and without vibration, eyes-open and eyes-closed, and with and without auditory Stroop test). The COP parameters were recorded as follows: range sideways and range fore-aft as well as mean velocity and area variables. The cognitive task parameters included the reaction time and error ratio. The intra-class correlation coefficient (ICC) was computed to assess the intersession reliability of COP parameters. RESULTS: in intersession, range sideways, range fore-aft, and mean velocity measures possessed moderate to high ICC, but area owned high ICC only in one condition (double-leg stance, eyes-close, with vibration, and with auditory Stroop test). Notably, other conditions had low ICC, and moderate to high and low to very high ICC were reported for reaction time and error ratio. CONCLUSION: Among the parameters studied in the present study, the mean velocity measure seems to be the most reliable variable of postural control in the subjects with NSLBP especially in more challenging conditions, i.e., quiet double-leg standing with eyes closed and adding vibratory inputs during dual-tasking.

Confirmatory Factor Analysis, Reliability, and Validity of the Persian Version of the Coping Strategies Questionnaire for Iranian People With Nonspecific Chronic Neck Pain.

OBJECTIVE: The purpose of this study was to assess the reliability and construct validity of, and perform confirmatory factor analysis of, the Persian version of the Coping Strategies Questionnaire (CSQ) for Iranian people with nonspecific chronic neck pain. METHODS: We performed psychometric testing of the Persian version of the Coping Strategies Questionnaire. Participants were 123 native Persian speakers with chronic neck pain lasting at least 3 months. They were between 18 and 55 years old. The CSQ was administered by self-report. After 5 to 7 days, 94 participants completed the questionnaire in the retest session. Confirmatory factor analysis was done to assess the model fit (χ2 test, comparative fit index, and root-mean-square error of approximation) of the 7-factor solution of the Persian version of the CSQ. The Cronbach α was used for internal consistency; intraclass correlation coefficient, standard error of measurement, and minimal detectable change for reliability; and nonparametric tests of group differences and correlations for construct validity. To assess the construct validity, we examined the ability of the CSQ to discriminate people based on sex, level of education, and physical activity. Correlations with the Short Form Health Survey (SF-12), Tampa Scale for Kinesiophobia, visual analog scale, Fear-Avoidance Beliefs Questionnaire, Pain Catastrophizing Scale, and Neck Disability Index were also determined to test the validity. RESULTS: Confirmatory factor analysis measures-χ2 test, comparative fit index, and root-mean-square error of approximation-were 1.72, 0.76, and 0.07, respectively. Internal consistency was excellent (0.85). All intraclass correlation coefficients were above the acceptable level of 0.70, with the highest reliability obtained for the Praying subscale in both test and retest sessions. The standard error of measurement for the CSQ total score was 2.26, and the minimal detectable change was 6.25. The Cronbach α for the total score and for the subscales ranged from 0.75 to 0.93. Scores of the subscales of the CSQ and other questionnaires showed low correlation except for the physical component of the SF-12. The Catastrophizing subscale had a positive correlation with the Pain Catastrophizing Scale, Tampa Scale for Kinesiophobia, Fear-Avoidance Beliefs Questionnaire, and Neck Disability Index, and a negative correlation with the SF-12. CONCLUSION: The CSQ has acceptable and good measurement properties to assess coping strategies in Iranian people with nonspecific chronic neck pain. It is a reliable measure, though, for validity only The Catastrophizing subscale showed significant correlation with other scales, but the findings should be interpreted with caution because of the limitations of the study.