Community-based cross-sectional survey
Kajiru Gad Kilonzo, Stefanie J. Krauth, Jo Halliday, Clive Kelly, Stefan Siebert, Gloria Temu, Christopher Bunn, Nateiya M Yongolo, Sally Wyke, Emma McIntosh, Richard W. Walker, Blandina Mmbaga
Abstract
This protocol details community-based cross-sectional survey.
Attachments
Steps
Participant selection
Based on sample-size calculations, the study will recruit 1050 households (approximately 5701 individuals) for this cross-sectional survey, to achieve a confidence level of 95% and assuming a 15% prevalence of MSK (as estimated in the pilot study).
Two-stage cluster sampling with replacement and probability proportional to the size of the village population will be used. (25)
In the first stage villages will be selected from a sampling frame, and one village can be selected more than one time with the probability of selection proportional to the size of the village. In the second stage, households will be selected with random probability.
The selection of households in the second stage benefits from the existing organisation of Tanzania households within Balozi, as the Balozi ‘informal’ infrastructure will be used to enumerate the households and to inform the households in the villages about the aims of the survey.
In addition, in the Moshi urban setting one street is selected using convenience sampling. All eligible members of selected households identified in the community setting will be invited to participate in the study and asked to provide written informed consent as described in the consent section below.
Data collection
A three-stage screening process for all participants will be followed (See Table 1: Summary of community-based research).
Table 1: Summary of community-based research
| A | B |
|---|---|
| Community survey: | |
| Setting | Randomly selected villages in HAI district & Majengo community in Moshi urban |
| Participants | Members of selected households (general population) |
| Research methods | Questionnaire surveys |
| Physical examinations | |
| Medical imaging & blood testing | |
| Instruments: | Tier 1: General (all participants): |
| (tiered according to GALS results) | GALS (Swahili version) |
| *denotes instruments applied to participants below 18 years of age | pGALS (Swahili version)* |
| WHO DAS (Swahili version) | |
| EQ5D (Swahili version) | |
| Demographic questionnaire | |
| Short health questionnaire | |
| Short health economics questionnaire | |
| CHU 9D (Swahili version)* | |
| Tier 2: GALS+ participants: | |
| HAQ (Swahili version) | |
| Global Health + modified Joint Pain Visual Analog scale (Swahili version) | |
| REMS | |
| pREMS* | |
| 66/68 swollen/tender joint count* | |
| Tier 3: REMS+/pREMS+ participants: | |
| Blood testing | |
| Ultrasound | |
| Long health economic questionnaire | |
| Additional health questions | |
| Further medical examinations (height, weight, blood pressure, details on identified MSK disorders) | |
| The Tier 2 and 3 tools (excluding medical imaging, bloods and further medical exams) will also be administered the GALS- control sample from Tier1 who are age and sex-matched to REMS+/66/68 joint count+ participants in Tier3 | |
| Community-based qualitative research | |
| Setting: | Randomly selected villages in HAI district |
| Participants: | Members of selected households (general population) |
| Research methods: | Focus groups (GALS+ community members) (Appendix 18) |
| Semi structured interviews (GALS+ community members) | |
| Visualisation methods | |
| Co-creation methods |
*A copy of all tools compiled into a single survey document can be requested from the authors.
In the first stage, all participants will be assessed using a version of the Gait Arms Legs Spine (GALS) screening test adapted for the local context and translated for delivery in Swahili. (26)
An adapted version of the paediatric version (pGALS) will be delivered in Swahili for those aged 5-17 years (27) who declare locomotor limitations or symptoms. The pGALS has previously been translated into Swahili, among other languages, and shown to be practical and acceptable in children in Malawi. (28)
In addition, All participants will be administered a demographic questionnaire, a short health questionnaire, and a short health-economics questionnaire (only participants >11 years).
Furthermore, adult participants (18+ years) will be administered the WHO Disability Assessment Questionnaire (WHO DAS), and the EQ-5D questionnaire (29,30), whereas minors under 18 will be administered the CHU 9D questionnaire (31).
Individuals who test negative in the GALS examination will be assessed whether they are of the same sex and similar age range as already-identified REMS+ participants and, if so, will be included as controls.
GALS- individuals who are not included as controls during their first visit will be asked for assent to be re-visited in case of further questions and will be revisited in case they are an appropriate control for a REMS+ case.
The second stage will be applied to GALS+ individuals as well as sex and age matched controls for REMS+ individuals and will include the modified Health Assessment Questionnaire (HAQ), and the Global Health questionnaire.
GALS+ individuals (but not controls) will be administered REMS and the 66/68 swollen/tender joint count + Joint Pain Visual Analog Scale (VAS).
In the third stage, all REMS+ individuals and controls will be administered the long health-economic questionnaire (only participants >11 years), be asked additional questions about their health including the presence of additional non-communicable diseases, and have their height, weight and blood pressure measured.
REMS+ individuals (but not controls) will have their blood taken for laboratory analysis. In addition, ultrasound imaging will be taken from all affected joints (see Laboratory and radiological data collection section) and additional details about the participants’ MSK disorders will be recorded.
