Alexandra M Curtis1, John VanBuren1,2, Joseph E Cavanaugh1,3, John J Warren4, Teresa A Marshall4, Steven M Levy4,5. 1. Department of Biostatistics, College of Public Health, The University of Iowa, Iowa City, IA, USA. 2. Division of Critical Care, Department of Pediatrics, School of Medicine, The University of Utah, Salt Lake City, UT, USA. 3. Department of Statistics and Actuarial Science, College of Liberal Arts, The University of Iowa, Iowa City, IA, USA. 4. Department of Preventive & Community Dentistry, College of Dentistry, The University of Iowa, Iowa City, IA, USA. 5. Department of Epidemiology, College of Public Health, The University of Iowa, Iowa City, IA, USA.
Abstract
OBJECTIVES: To assess longitudinal associations between permanent tooth caries increment and both modifiable and non-modifiable risk factors, using best subsets model selection. METHODS: The Iowa Fluoride Study has followed a birth cohort with standardized caries exams without radiographs of the permanent dentition conducted at about ages 9, 13, and 17 years. Questionnaires were sent semi-annually to assess fluoride exposures and intakes, select food and beverage intakes, and tooth brushing frequency. Exposure variables were averaged over ages 7-9, 11-13, and 15-17, reflecting exposure 2 years prior to the caries exam. Longitudinal models were used to relate period-specific averaged exposures and demographic variables to adjusted decayed and filled surface increments (ADJCI) (n = 392). The Akaike Information Criterion (AIC) was used to assess optimal explanatory variable combinations. RESULTS: From birth to age 9, 9-13, and 13-17 years, 24, 30, and 55 percent of subjects had positive permanent ADJCI, respectively. Ten models had AIC values within two units of the lowest AIC model and were deemed optimal based on AIC. Younger age, being male, higher mother's education, and higher brushing frequency were associated with lower caries increment in all 10 models, while milk intake was included in 3 of 10 models. Higher milk intakes were slightly associated with lower ADJCI. CONCLUSIONS: With the exception of brushing frequency, modifiable risk factors under study were not significantly associated with ADJCI. When possible, researchers should consider presenting multiple models if fit criteria cannot discern among a group of optimal models.
OBJECTIVES: To assess longitudinal associations between permanent tooth caries increment and both modifiable and non-modifiable risk factors, using best subsets model selection. METHODS: The Iowa Fluoride Study has followed a birth cohort with standardized caries exams without radiographs of the permanent dentition conducted at about ages 9, 13, and 17 years. Questionnaires were sent semi-annually to assess fluoride exposures and intakes, select food and beverage intakes, and tooth brushing frequency. Exposure variables were averaged over ages 7-9, 11-13, and 15-17, reflecting exposure 2 years prior to the caries exam. Longitudinal models were used to relate period-specific averaged exposures and demographic variables to adjusted decayed and filled surface increments (ADJCI) (n = 392). The Akaike Information Criterion (AIC) was used to assess optimal explanatory variable combinations. RESULTS: From birth to age 9, 9-13, and 13-17 years, 24, 30, and 55 percent of subjects had positive permanent ADJCI, respectively. Ten models had AIC values within two units of the lowest AIC model and were deemed optimal based on AIC. Younger age, being male, higher mother's education, and higher brushing frequency were associated with lower caries increment in all 10 models, while milk intake was included in 3 of 10 models. Higher milk intakes were slightly associated with lower ADJCI. CONCLUSIONS: With the exception of brushing frequency, modifiable risk factors under study were not significantly associated with ADJCI. When possible, researchers should consider presenting multiple models if fit criteria cannot discern among a group of optimal models.
Authors: Sungwoo Lim; Woosung Sohn; Brian A Burt; Anita M Sandretto; Justine L Kolker; Teresa A Marshall; Amid I Ismail Journal: J Am Dent Assoc Date: 2008-07 Impact factor: 3.634
Authors: Teresa A Marshall; Alexandra M Curtis; Joseph E Cavanaugh; John J Warren; Steven M Levy Journal: J Acad Nutr Diet Date: 2020-10-24 Impact factor: 4.910