Criterion validity and reliability of SF-12 health survey version 2 (SF-12v2) in a student population during COVID-19 pandemic: a cross-sectional study

Objective. The novel coronavirus SARS-CoV-2, responsible for the COVID-19 pandemic, led to strict domestic quarantine, social isolation policies, and consequently significant psycho-emotional and lifestyle changes. The individual and societal fear and anxiety cause significant stress affecting health-related quality of life (HRQOL). There is evidence of the psychological and mental health effects of the current pandemic on students, who are known to be a vulnerable population. A decrease in physical activity was reported among students, and it is known to contribute to stress levels, which is strongly associated with HRQOL. This study is aimed at evaluating the validity and reliability of SF-12 Health Survey version 2 (SF-12v2) in the assessment of self-perceived quality of life of Italian students following lifestyle changes due to the outbreak of COVID-19. Methods. A cross-sectional study was conducted with university students attending the faculty of Medicine and Surgery or Health Professions. The Physical Component Summary (PCS12) and the Mental Component Summary (MCS12) of SF-12v2 were compared to the Perceived Stress Scale (PSS). Internal consistency was examined using Cronbach's Alpha Coefficient. Concurrent validity was evaluated comparing SF-12v2 values to PSS scores, and the Pearson Correlation Coefficient (PCC) was calculated. Cross-cultural validity was investigated through several analyses for correlations between SF-12v2 scores and the gender of participants, University of Italy, body mass index (BMI), and time spent sitting and exercising. Results. The SF-12v2 questionnaire was administered to 583 medical and health professionals' students in July 2020. Cronbach's Alpha showed acceptable reliability for PCS12 and MCS12. In line with expectations, PCS12 scores differed by BMI groups, while the MCS12 was associated with PSS score and showed differences between genders, BMI groups, time spent sitting, and time spent exercising. Conclusion. The Italian version of SF-12v2 is a valid and reliable instrument to assess health-related quality of life among medical and health professionals' students.