Background: Data in national health care quality registries must be valid and reliable in order to enable open comparisons of results.
Aim: To assess the reliability of data on percent consonants correct (PCC) and its associated quality indicator ≥86% correct consonants in the Swedish quality registry for patients born with cleft lip and palate (CLP) registry.
Methods: Six independent speech-language pathologists re-assessed the audio recordings of 96 five-year-olds with PCC data in the CLP registry. Target consonants of a single-word picture-naming test were phonetically transcribed, and PCC was calculated. The reliability of PCC data was assessed with the intraclass correlation coefficient (ICC). The reliability of the quality indicator ≥86% correct consonants was assessed with point-by-point percentage agreement and Cohen's kappa.
Results: Intra- and inter-judge agreement for PCC was excellent with ICCs above 0.9, and so was the agreement of data from the CLP registry and the six judges' re-assessments. The percentage agreement between all judges and the CLP registry for the quality indicator ≥86% correct consonants was poor (67%). However, in 88% of the cases, results from four judges and the CLP registry agreed, corresponding to good agreement. The mean of all kappa values for six judges and the CLP registry corresponded to good agreement (0.72).
Conclusions: The results indicate the PCC data in the CLP registry and the quality indicator ≥86% correct consonants to be reliable. When differences in outcome between treatment centres are detected, the raw data collected should always be re-examined before drawing definitive conclusions.
Keywords: Percent consonants correct; cleft lip and palate; quality registry; reliability.