Development and preliminary validation of a novel chest wall specific quality of life instrument-C-QoL.

Abstract

Quality of Life (QoL) is a core metric for patients with chest wall injury (CWI). No thoracic specific QoL instruments exist and granularity to assess impact of interventions on patients with chest wall injury is lacking. We hypothesized we could develop a valid and reliable CWI specific quality of life (C-QoL) questionnaire. A systematic review of QoL instruments used in chest wall injury literature was performed and an international group of CWI experts assembled a panel of questions for inclusion. A three-round modified Delphi consensus process was performed using a 70% consensus threshold. A clinical validation study enrolling adults with ≥1 rib fractures(s) was performed. Participants completed the C-QoL and the SF-36 twice, with a week intervening each response. Reliability, construct validity, floor and ceiling effects of the C-QoL (sub)scales were determined using the COnsensus-based Standards for the selection of health Measurement Instruments group guidelines. Twenty-two CWI experts participated in the Delphi process resulting in creation of the C-QoL instrument with five domains: pain, physical functioning, general health, socio-economic functioning, and psychological health. Scores ranges from 0 to 100. Median QoL score for the first 154 participants was 34 (P25-P75 25-50). Subscale scores ranged from 29 (P25-P75 14-48) for pain to 55 (P25-P75 37-75) for psychological health. All (sub)scales showed an inverse correlation with injury severity and had adequate reliability (Cronbach alpha between 0.70 and 0.95), construct validity (>75% or correlations with SF-36 (sub)scales are predicted correctly) and had no floor or ceiling effect. The C-QoL instrument is reliable and valid for measuring CWI specific QoL in patients. A prospective study is needed to externally validate the instrument, and to determine the responsiveness, measurement error, and minimal important change. Diagnostic Tests or Criteria; Level II.