Rasch analysis suggested that items from the template for intervention description and replication (TIDieR) checklist can be summed to create a score.

ABSTRACT

OBJECTIVE: The aim of this study was to construct and evaluate a summary score of reporting completeness based on the Template for Intervention Description and Replication (TIDieR). STUDY DESIGN AND SETTING: We included 200 reports published in 2013 randomly selected from the Physiotherapy Evidence Database. We summed the scores for the 12 items for the intervention and control groups for each trial to create a summary score from 0 to 24. Rasch analysis was used to investigate the item hierarchy, category function and reliability of the TIDieR checklist and determine the extent to which the summary score can be considered an interval-level measure. RESULTS: The data fit the Rasch model suggesting the summary score is able to assess the completeness of reporting. The items appeared to target the study sample well (average report measure was 0.48 [0.87] compared to the average item measure of 0.0 [1.82]), and progressed in a logical manner, suggesting the summary score can be used as a single variable. The low internal consistency (0.62) suggests the summary score may only be able to discriminate between the least and most detailed reports. CONCLUSIONS: Our results support the use of the TIDieR summary score; however, we encourage the replication of our study in an independent data set.