PERSIAN Traffic Safety and Health Cohort: a study protocol on postcrash mental and physical health consequences

Quality of Life and Socioeconomic Status in Northwest of Iran: First Wave of the Persian Traffic Cohort Study

This study aimed to evaluate the association between Quality of Life (QOL) and independent factors, emphasizing Socio Economic Status (SES) in northwestern Iran. A population-based cross-sectional study was performed within the Persian Traffic safety and health Cohort in 2020. Participants were chosen using stratified random sampling method. The majority of participants (69%) were aged between 30 and 65. Around half of the participants were males (54.44%). Most of the female respondents were categorized as very low and medium levels of SES Based on multiple linear regression analysis, the QOL among females was lower compared to males (β: - 0.92, 95% CI - 1.82 to - 0.22). There was a negative association between SES and QOL; individuals with low and very low levels of SES had a lower QOL than those with a medium level of SES (β: - 4.38, 95% CI - 5.9 to - 2.86) (β: - 2.65, 95% CI - 4.08 to - 1.22). The current study highlights that higher SES and educational levels are positively associated with higher QOL. Conversely, older age, females, and widowed individuals are linked with lower QOL.

Psychometric properties of the 12-item WHODAS applied through phone survey: an experience in PERSIAN Traffic Cohort

BACKGROUND

Due to limited capability to function in post-injury daily life injury, survivors need to be reliably assessed without need to commute more than necessary. The key action is to determine the level of functioning difficulties. Having the opportunity of conducting a national post-crash traffic safety and health cohort study, we aimed to translate into Persian and assess the psychometric properties of the World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) through phone surveys six month post injury.

METHODS

First, having World Health Organization permission, we tested the translation validity by forward translation, expert panel evaluation, back-translation, pre-testing and cognitive interviewing, and finalizing the Persian WHODAS. Then, through a psychometric study within a national cohort platform, the validity, reliability and applicability of the 12-item WHODAS was assessed through phone surveys. We included data of 255 road traffic injury patients enrolled from the cohort at six-month follow-up. The psychometric assessment (internal consistency reliability and stability reliability) was conducted on test-retest data of 50 patients with an average 7-day time span. An exploratory factor analysis tested the construct validity using extraction method of principal component factor and oblique rotation on data from 255 patients. Regarding the multiple criteria including an eigenvalue > 0.9, Cattell's scree test, cumulative variance, and the theoretical basis, the minimum number of factors were retained. Data were analyzed using STATA statistical software package.

RESULTS

The respondents were mostly male (81%), employed (71%), educated (87%), and with a mean age of 37.7(14.9). The Persian version had high internal consistency reliability (Cronbach's α = 0.93) and excellent stability reliability (ICC = 0.97, 95% CI: 0.92-0.98). An exploratory factor analysis retained four factors defining 86% of all the variance. Factors of Self-care, Mobility, and Cognition were completely retained.

CONCLUSIONS

The brief Pesrian WHODAS 2.0 was highly reliable and valid to be applied through phone interviews post injury.