We conducted a quantitative cross-sectional study between November and December 2020. Healthcare providers were recruited from 10 ODs with low and 10 ODs with high childhood TB case detection in 13 provinces. In each OD, there is one referral hospital (RH) covering about 100,000 population and several health centers (HCs), each serving about 10,000 population (10). We purposively selected the 20 ODs to ensure equal representation of urban and rural localities. In the selected study sites, there were a total of 20 RHs and 208 HCs.
At the RHs, the number of healthcare providers varies depending on the level of RHs. Complementary package activities 1 (CPA1) refers to RHs with "no grand surgery (without general anesthesia); CPA2 refers to RHs with grand surgery and emergency care services; and CPA3 refers to RHs with grand surgery and various specialized services such ears, nose, and throat (ENT) and ophthalmology (11). Six physicians working directly or indirectly on TB in each RH were selected for the interviews. With an assumption of 10% of the non-response rate, the minimum required sample size was 132. However, if more than six physicians were working directly or indirectly with childhood TB, all of them would be selected for interviews.
In the Minimum Package of Activities (MPA) for HC Development 2007, the minimum number of staff required to ensure the proper function of an HC is at least eight people (12). Healthcare services provided at HC include outpatient consultation services; maternal, newborn, child, and reproductive health services; infectious diseases services; non-communicable diseases services; and health education and health promotion services (12). In Cambodia, at least two outpatient consultation and communicable disease service staff were directly or indirectly linked to childhood TB services. Therefore, among the 208 HCs in the selected ODs, at least 416 HC staff were eligible. With a 5% margin error, 95% confidence interval (CI), and 50% of HC staff correctly identified and referred presumptive childhood TB cases to RHs for TB diagnosis, and a 10% non-response rate, the minimum required sample size was 220. With two staff to be selected from one HC, 110 HCs were randomly selected. The selection of HCs was based on the proportion of the number of HCs in each OD.
Data collection procedures
The questionnaire was initially developed in English and then translated into the Khmer language. It was then pretested and revised accordingly before being administered by trained data collectors. The interviews were face-to-face using a paper-based questionnaire, and each interview took about 30 to 40 min to complete. Respondents received a compensation gift valued at about one US dollar. The data collection team leader checked the collected data for completeness and accuracy.
Variables and measurements
A structured questionnaire was developed based on tools adapted from a previous study (7), a childhood TB treatment guideline training manual developed by NTP (13), and the current TB-Speed research project implemented by Institut Pasteur du Cambodge through an oral communication with the NTP in February 2020. The tools were tailored to the study settings and objectives through discussions with a research team at the National Center for Tuberculosis and Leprosy Control (CENAT). Socio-demographic characteristics included age, sex, education, role at the health facility (head of HC or TB staff), departments (infectious diseases, outpatient department or consultation services, medical ward, surgical ward, pediatric ward, or emergency ward), and training on childhood TB. Knowledge on childhood TB included the causes of TB, transmission routes, signs and symptoms, characteristics of lymph nodes that implied TB, and diagnostic criteria for childhood TB. For attitude, we collected participants' perceptions on contact investigation, training on childhood TB, TB diagnostic tools, laboratory services, and human resources for childhood TB. Information on practices included contact investigation performance, presumptive TB referrals for diagnostic work-ups, and TB treatment. Attitude and practices were measured using four levels of the Likert scale (14). We used four levels of respondents' agreement—"strongly agree," "agree," "disagree," and "strongly disagree")—for each of the seven statements toward childhood TB case detection to measure respondents' attitude. Similarly, four statements about practices toward childhood TB case detection were captured using "always," "often," “sometime,” or “never.”
After data cleaning, recoding was done for some variables. We grouped categories for age, knowledge on TB signs and symptoms, knowledge on groups of children at high risk of developing TB, characteristics of lymph nodes implied TB, and screening criteria for childhood TB to facilitate the subsequent analyses. For attitudes, respondents who answered "always" and "often" to the statements were considered to have a positive attitude towards childhood TB case detection. Similarly, good practices were classified when respondents answered “always” and “often” to the positive statements toward childhood TB case detection.
Data management and analyses
Collected data were double entered into EpiData 3.1 (The EpiData Association, Odense, Denmark) and then exported into STATA 14.2 (Stata Corp, College Station, Texas). Respondents were categorized into two groups based on whether they were from ODs with high and low childhood TB case detection. Knowledge on childhood TB was categorized as follows: knowing symptoms and signs of childhood TB (<4 vs. ≥4), knowing characteristics of enlarged lymph nodes implied TB (<3 vs. ≥3), and knowing screening criteria for childhood TB (<4 vs. ≥4).
Descriptive analyses were conducted to calculate frequency and proportion for categorical variables and mean and standard deviation (SD) for continuous variables. In bivariate analyses, we used Pearson's Chi-square (or Fisher’s exact test when a cell count was smaller than five) for categorical variables and Student’s t-test for continuous variables to explore the differences in characteristics and KAP of healthcare providers from ODs with low vs. high childhood TB detection. A p<0.05 was considered statistically significant.
This study was conducted after obtaining ethical clearances from the National Ethics Committee for Health Research (NECHR) in Cambodia (ref. 234/NECHR) and the Ethics Review Committee of the World Health Organization Western Pacific Regional Office (WPRO-ERC) (ID: 2020.8.CAM.3.STB). All methods were carried out in accordance with national guidelines and regulations. The objectives, procedures, risks, and benefits in participating in this study were explained to each participant. All participants provided a written informed consent for the study. Data from all participants were treated anonymously, without a name, address, and personal information in the records. Information provided was handled strictly confidential.