Validity and reliability of the Persian version of the short-form child perceptions questionnaire 11-14-year-old children (CPQ11-14).

BACKGROUND: The Child Perception questionnaire 11-14 (CPQ 11-14) is an efficient tool for assessment of oral health-related quality of life (OHRQoL). This questionnaire has been briefed to 16 items (CPQ11-14 ISF-16) to facilitate its employment. The purpose the present study was to translate CPQ11-14 ISF-16 to Persian language, culturally adapt, and initially evaluate its among adolescent population. MATERIAL AND METHOD: The questionnaire has been translated to Persian, then back-translated to English, and finally underwent cultural adaptation and pretesting assessment. It was then filled out by 318 participents (175 grils and 143 boys), with the age of 11 to 14 years resident in Shiraz, Iran. The Persian version of CPQ11-14 ISF-16 along with the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) and two suggested global questions were administered among participants to assess its criterion validity. RESULTS: The factor analysis extracted two domains and the factor loading of domains ranged from 0.423 to 0.837. Persian version of CPQ11-14 ISF-16 presented high internal consistency (Cronbach's alpha = 0.854), and showed excellent criterion validity with PIDAQ (rho = 0.731, p < 0.001). There was a statistically significant positive moderate correlation between CPQ11-14 ISF-16 and its factors 1 and 2 and two global questions (first global question: rho = 0.439, p < 0.001; second global question: rho = 0.457, p = 0.035). CONCLUSION: The Persian version of CPQ11-14 ISF-16 has optimal validity and reliability in a general population of 11-14-year-old Persian children.

The impact of age mimicry bias on the accuracy of methods for age estimation based on Kvaal's pulp/tooth ratios: a bootstrap study.

INTRODUCTION: Methods based on pulp/tooth ratios proposed by Kvaal et al. (1995) have been widely used for age estimation in adults. The tendency of age estimates to mimic the age structure of the reference population, i.e. age mimicry bias, is a possible source of controversy in the results of studies. The primary objective of the present study was to evaluate the effect of age mimicry bias on the accuracy of the original Kvaal's method and its recent modification proposed by Roh et al. (2018). METHOD AND MATERIAL: The study sample comprised 240 cone-beam computed tomography scans of an Iranian population. The bootstrap procedure was used to study the impact of age mimicry bias on age estimates by constructing reference populations with different age structures. The accuracy of Kvaal's and Roh's variables for age estimation was assessed using a twofold cross-validation technique and principal component analysis. RESULTS: The application of original equations resulted in SEE values highly greater than the acceptable threshold for forensic purposes (10 years). The population-specific equations obtained SEE values of 9.18, 11.03, and 9.22 years using Kvaal's variables and 9.19, 11.13, and 9.14 years using Roh's variable for the maxillary, mandibular, and all teeth, respectively. The bootstrap procedure revealed that using uneven reference populations to formulate the equation resulted in significantly greater SEEs (almost all >10 years) that were not acceptable for forensic purposes. Moreover, using an older (a younger) reference population contributed to a sharp rise in the amount of over- (under-) estimation for younger (older) age groups. CONCLUSION: Age mimicry bias had an undesirable impact on the accuracy of dental age estimation based on Kvaal's and Roh's methods. The accuracy of the original equations was low for age estimation in the Iranian sample. However, the performance of the population-specific equations was reasonably acceptable for the maxillary and all six teeth.