치과위생사 구인난과 치과의사의 근무시간 조정 지원 선택: 2021년 한국 설문자료의 2차 분석

This record contains the preregistered protocol for a secondary, cross-sectional analysis of the 2021 Korean Dental Association member survey. The study will examine whether dentists’ perceived difficulty recruiting dental hygienists and the reported time required to recruit them are associated with selecting work-time adjustment as a support option for the re-employment of inactive personnel. The final analytic dataset includes 2,223 survey respondents. The primary analysis is restricted to respondents who considered the use of inactive personnel necessary (policy_2 = 1; n = 1,955). The binary outcome is selection of work-time adjustment support from a multiple-response item (policy_2_2_time): within this eligible branch, 1 indicates selected and 0 indicates not selected. Respondents outside the branch have structural missing values and will not be recoded as non-selectors. The primary hypothesis (H1) concerns the association between perceived recruitment difficulty (diffi_dh, modeled as a continuous 0–10 score) and support selection. The secondary hypothesis (H2) concerns reported recruitment duration (emp_duration, modeled as a five-category factor). Separate multivariable logistic regression models will adjust for dentist age, sex, specialty, region, number of dentists, and chair count. H1 is primary and H2 secondary; Holm adjustment will be applied across the two hypothesis tests. Results will include adjusted odds ratios, 95% confidence intervals, and standardized predicted probabilities. Age- and sex-related differences are exploratory. All estimates will be interpreted as cross-sectional associations, not causal effects. This is a secondary analysis of the same survey dataset used in Lee, Jeon, and Han (2021), which reported dental workforce recruitment conditions and differences by clinic size. That reuse and the research team’s prior knowledge are disclosed in the protocol. The authors report that this specific exposure-outcome combination had not been examined before preregistration. The survey response rate was 8.3%; selection and nonresponse bias, limited representativeness, and the absence of clinic identifiers are acknowledged. The respondent-level dataset is not included in this record. The survey was approved by the Institutional Review Board of the Seoul National University School of Dentistry (S-D20200054). The work was carried out in accordance with the Declaration of Helsinki; participants gave informed consent online, and anonymity was preserved. The funders did not access the data and had no role in study design, analysis, interpretation, or manuscript preparation. The authors and researchers report no conflicts of