Validation of a single-item stem for collective efficacy measurement in sports teams

 The validity and reliability of an operational stem for single-item collective efficacy measurement were examined across three studies in sport. Study 1 used a cross-sectional design with team sports participants to assess the stem's validity by examining the ability of the Collective Efficacy Questionnaire for Sports (CEQS), Group Environment Questionnaire (GEQ), and previous performance (win %) to predict single-item collective efficacy scores. Total CEQS scores predicted single-item scores (β = .69), with the CEQS Ability (β = .51) and Persistence (β = .15) subscales the only significant predictors of single-item score. Previous performance (β = .41) and three GEQ dimensions, Individual Attractions to the Group-Task (β = .18), Group Integration-Task (β = .22), and Group Integration-Social (β = .16), were also significant predictors of single-item collective efficacy. Study 2 examined the validity and reliability of the stem using an intervention with team sports participants in a laboratory-based design. The single-item measure demonstrated high concordance (pre-intervention; r = .53, post-intervention; r = .73) and reliability (r = .77, .62) with CEQS scores. Study 3 assessed the validity and reliability of the stem using an intervention with team sports participants in a field-based design. The single-item measure reported high concordance (pre-intervention; r = .74, post-intervention; r = .69) and reliability (r = .88, .87) with CEQS scores. The studies support the stem as valid and reliable for single-item collective efficacy measurement with team sports players.