A single‐item measure of social identification: Reliability, validity, and utility

TLDR

Short measures often fail to achieve acceptable reliability because the constructs they assess are broad and heterogeneous. The study introduces a single‑item social identification measure (SISI) and conducts a meta‑analysis of 16 widely used single‑item scales to examine their reliability. SISI is rated on a 7‑point agreement scale, and its validity was examined in three studies, while a meta‑analysis assessed the reliability of 16 single‑item measures. The three studies demonstrate good convergent, divergent, and test‑retest validity for SISI, with an overall reliability comparable to the high end of single‑item scales, suggesting that social identification is homogeneous enough for a single‑item operationalization.

Abstract

This paper introduces a single‐item social identification measure ( SISI ) that involves rating one's agreement with the statement ‘I identify with my group (or category)’ followed by a 7‐point scale. Three studies provide evidence of the validity (convergent, divergent, and test–retest) of SISI with a broad range of social groups. Overall, the estimated reliability of SISI is good. To address the broader issue of single‐item measure reliability, a meta‐analysis of 16 widely used single‐item measures is reported. The reliability of single‐item scales ranges from low to reasonably high. Compared with this field, reliability of the SISI is high. In general, short measures struggle to achieve acceptable reliability because the constructs they assess are broad and heterogeneous. In the case of social identification, however, the construct appears to be sufficiently homogeneous to be adequately operationalized with a single item.