Prácticas Espirituales

4.2.5.1 Pilot questionnaire

The study questionnaire (Appendix 8) was constructed using the World Health Organization (WHO) STEPwise approach to surveillance of non-communicable diseases (STEPS). ¹ The STEPS questionnaire was chosen based on prior knowledge because it was used to collect data in PNG two years prior to the current study. Data collected from participants with T2DM (current study) was to be compared with data from the non-T2DM participants of the STEPS study to meet the objectives of the study as a whole. Questions on betel nut use within the STEPS questionnaire were expanded and questions on medication and some biochemical measurements were added into the instrument. Some questions on social behaviour were modified to achieve the aims of the study. For example, the STEPS survey asked participants how many times they used betel nut daily while the current study asked participants how many betel nuts they chewed per day. This question was modified based on prior knowledge that some betel nut chewers chew more than one nut each time they chew betel nut. Data collected included demographic information, behavioural measurements (betel nut chewing, vegetable and fruit consumption, physical activity, smoking and alcohol consumption), physical measurements (height, weight, waist and hip circumferences and blood pressure), biochemical measurements (fasting/random blood glucose, HbA1c, lipid profile, urea, creatinine, and urine protein and glucose) and diabetes management. Certain items in STEPS, such as Oral Glucose Tolerance tests and questions on oral health were not included in the questionnaire. The questionnaire was pretested at the PMGH Diabetes Clinic.

4.2.5.2 Final questionnaire

The pretesting of the questionnaire did not result in any changes in the questionnaire.

4.2.5.3 Interviews

Data were collected using face-to-face interviews. All responses were entered onto the questionnaire used. Show cards used in the STEPS (Appendix 9) survey also

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were used to clearly explain terms such as servings of fruits and vegetables, and quantities of alcohol. During the pretesting of the questionnaire, it was found that participants were not able to understand the term “serving” and when this was equated to a cup, they could not visualise a cup. In PNG, the usage of the word

“cup” is not specific to cup as a measure and it commonly includes a mug as well.

To visualize a cup as a measure, a measuring cup was used to guide the participants in estimating the quantity of vegetable and fruit they consumed. The number of cups was entered onto the questionnaire and was later converted to number of servings before data entry using the STEPS show card.

4.2.5.4 Clinic Cards

Participants’ clinic cards were used to validate some of the responses and information required, such as names of medications, their doses, date of birth, suburb of residence, pathology tests, and year of diagnosis and/or registration at the Diabetes Clinic

.

4.2.5.5 Measurement of HbA1c

HbA1c was measured using the Point-of-Care Siemens/Bayer DCA 2000 Vantage™

analyser (Siemens Medical Solutions USA Inc, Palvern, PA, USA). This machine was only able to measure HbA1c to 14.0%, so any reading more than 14.0% was given as >14.0% with no specific reading. During data entry, this was entered as 15.0% to indicate a reading in excess of 14.0%.

4.2.6 Sample size and sampling

The objectives of the study were to estimate the prevalence of betel nut chewing and to develop regression models to identify factors associated with betel nut chewing and glycaemic control. A sample size of N=385 should lead to an estimate of prevalence with a 95% confidence interval of no more than +/-5%. The confidence interval would be widest if the prevalence estimate was near 50%, and it would be narrower when it is either lower or higher than this. For the regression model, a sample of this size would be adequate to identify any independent

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variables exhibiting a small to moderate effect size.² Hence, the study aimed to recruit N=385 participants. The method of sampling was convenience sampling.

4.2.7 Ethics

Patients were provided with a PIS (Appendix 6) to read before they were asked if they wanted to participate. The PIS was written in English or orally translated into Pidgin English to those who requested it. Patients also were asked whether they wanted the interview in English or Pidgin English before the interview commenced.

Only those eligible patients who consented were recruited for the study. Consent forms were signed by both the interviewer and the participant before the interview began.

Approval for the study was granted by the Curtin University Human Research Ethics Committee [(HR 38/2011) Appendices 1,3)], The University of PNG School of Medicine and Health Sciences Research and Ethics Committee (Appendix 4) and the Medical Research Advisory Committee of the National Department of Health of PNG (Appendix 5). Permission to undertake the study at the Diabetes Clinic at the PMGH was granted by the Chief Executive Officer of the hospital.

4.2.8 Statistical analysis

Data were entered into an Excel dataset and transferred into SPSS versions 20/21 statistical software for analysis. Simple descriptive statistics (frequencies and percentages or means and standard deviations, or medians and ranges, as appropriate) were used to summarise demographic and lifestyle factors, physical measurements, diabetes management and biochemical measurement variables.

4.2.8.1 Univariate analyses

The statistical significance of differences in betel nut chewing habits according to demographic factors including age, gender, suburb of residence, region of origin, level of education, employment status and lifestyle factors were assessed using the Chi-square statistics. Similarly, univariate differences in glycaemic control between demographic variables, as well as lifestyle factors, physical activity, diabetes management and physical measurements such as body mass index (BMI) and

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blood pressure, also were assessed using these tests. Univariate logistic regression models were used to investigate the direction of the associations for different categories of each variable.

4.2.8.2 Multivariate analyses

Multiple Logistic Regression models were developed to identify which (if any) of the:

i) demographic and lifestyle variables were independently associated with the prevalence of betel nut chewing; and

ii) demographic, lifestyle, biochemical, physical measurement and diabetes management variables were independently associated with poor glycaemic control (HbA1c>7.0%).

The results of regression analysis were presented as Odds Ratios, along with their 95% confidence intervals and p-values. Following convention, a p-value of <0.05 was taken to indicate a statistically significant association in all tests.

4.3 Results

4.3.1 Study setting

Apart from provincial divisions, PNG also is divided into four regions. These regions are Southern, New Guinea Islands (NGI), Momase and Highlands as shown in Figure 4.2. Port Moresby, the national capital of PNG is situated in the Southern region. Port Moresby is not only the national capital of PNG but is also the capital of the Central Province. The Central Province has its headquarters in Port Moresby but the administration is responsible for affairs of the Central Province only. The administrative unit of the city of Port Moresby is the National Capital District (NCD) and the administrative authority of the city is the NCD Commission. Although not a province as such, NCD is classified as the equivalent of a province.

Each province in PNG has a provincial hospital, except for the two newly established provinces of Jiwaka and Hela. The largest hospital in the country is the PMGH. This hospital not only serves those who live in the city but also those who live in the rural areas of the Central Province. Furthermore, this is the country’s

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referral hospital, where all medical or surgical cases which cannot be dealt with in other provincial hospitals are managed.

Not all provincial hospitals have specialist diabetes clinics. When that is the case, patients with diabetes are usually cared for in general internal medicine clinics.

There are five diabetes clinics in PNG, of which four are in Port Moresby. Of all these clinics, PMGH Diabetes Clinic is the largest. The clinic not only cares for patients who live in Port Moresby but also those from other provinces in the country who have registered at the clinic.

During the time of the study, the PMGH diabetes clinic was run once a week for three hours on Tuesday mornings. The consultation rooms are shared with other internal medicine specialties and paediatrics and, therefore, clinics for these specialties are usually rostered to run on a weekly basis.