Development and validation of a condition‐specific measure for chronic periodontitis: Oral health impact profile for chronic periodontitis

Aim The aim of this study was to develop and validate the first condition‐specific tool to assess oral health‐related quality of life ( OHRQ oL) impairment in association with chronic periodontitis and to use it as an outcome measure in clinical trials. Methods Twenty‐three potential items were developed using a combined method consisting of a literature review, semi‐structured patient interviews ( n  = 20) and expert panel 1. Subsequently, item selection was carried out by means of qualitative content analysis and quantitative classical test theory ( CTT ) with 110 patients and expert panel 2. Consequently, 18 items were selected and included in the final oral health impact profile for chronic periodontitis ( OHIP ‐ CP ) instrument. The validity and reliability of the OHIP ‐ CP were then examined. Results A total of 238 patients participated in the validation phase of OHIP ‐ CP . The final 18‐item questionnaire was shown to have a three‐domain structure. The three components “pain and functional limitation”, “psychological discomfort” and “psychological disability and social handicap” explained 49.9%, 9.9%, and 6.2% of the variance, respectively, together accounting for 66.1% of the variance. In addition, the OHIP ‐ CP was shown to be valid in distinguishing patients with varying severity of chronic periodontitis. For the convergent validity, the reported impact of chronic periodontitis based on the OHIP ‐ CP significantly correlated with the global oral health rating. All of its three domains were found to have good levels of internal consistency with Cronbach's alpha >.7, and excellent test‐retest reliability. Conclusion The OHIP ‐ CP is the first condition‐specific OHRQ oL instrument for patients with chronic periodontitis. This short, reliable and valid questionnaire may serve as a valuable tool in future clinical trials.