Validation of the Primary Care Patient Measure of Safety (PC PMOS) questionnaire

BackgroundThe Primary Care Patient Measure of Safety (PC PMOS) questionnaire was developed to collect patient feedback on 15 latent conditions in the primary care environment that influence safety incidents. It provides a way for primary care organisations to learn about safety from the patient perspective, and to then make service improvements with the aim of reducing harm in this setting.AimTo undertake validation testing PC PMOS questionnaire.Method490 adult patients from nine general practices completed the PC PMOS, and 81 practice staff completed the AHRQ medical office survey on patient safety culture. Confirmatory factor analysis (CFA) was undertaken to assess the reliability and validity of the 10 factor PC PMOS.ResultsCFA demonstrated data did not fit the model well (CMIN/DF = 5.68; GFI = 0.61, CFI = 0.57, SRMR = 0.13 and RMSEA = 0.10), thus post hoc model fitting was conducted. This resulted in the removal of 22 items on the basis of large MIs (above 10), and SRs > ±2.58, and assessment of item content. The resulting 9 factor model consisting of 28 items was found to fit the data satisfactorily (CMIN/DF = 2.51; GFI = 0.87, CFI = 0.91, SRMR = 0.04 and RMSEA = 0.05). The new factors demonstrated good internal reliability. The PC PMOS did not demonstrate good convergent validity with the correlation between total PC PMOS score and practice staff patient safety score failing to reach statistical significance (r = −0.64, k = 9, P = 0.06). It demonstrated good discriminant validity between primary care practices (F = 2.64, df = 72, P<0.001).ConclusionValidation of the PC PMOS has led to a reliable and valid 28 item patient measure of patient safety in primary care. It could enhance or complement current data collection methods used in primary care to identify and prevent error, and is also a practical response to the growing need to find appropriate and effective ways of involving patients in improving patient safety.