Protocol design and registration

The review protocol has been registered on the International Prospective Register of Systematic Reviews database (http://www.crd.york.ac.uk/PROSPERO), registration number CRD420250651525.This scoping review will follow the Joanna Briggs Institute (JBI) manual for scoping reviews and adhere to the reporting standards outlined in the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) [20,21]. The methodology will be guided by a six-staged framework proposed by Arksey and O’Malley [22], which includes: (1) identifying the research question, (2) identifying relevant studies, (3) study selection, (4) charting the data, (5) collating, summarizing, reporting results, and (6) consultation with tuberculosis experts. The optional sixth stage is conducted parallel with earlier stages [23].

Stage 1: Identifying the research question

The primary question for the review is “What are the barriers and facilitators to tuberculosis (TB) treatment adherence among nomadic populations in Sub-Saharan Africa?”

The sub-questions are:

1. What are the key socio-cultural, environmental, and structural barriers to TB treatment adherence among nomadic populations in Sub-Saharan Africa?
2. How do stigma and discrimination associate with TB and HIV influence healthcare-seeking behavior and TB treatment adherence in nomadic communities?
3. What interventions or strategies have been effective in overcoming barriers to TB treatment adherence in nomadic populations, and what factors contribute to their success?

The study will employ the Population, Concept and Context framework, to determine the eligibility of the research questions (Table 1)

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Table 1. Population, concept and context relating to the research question.

https://doi.org/10.1371/journal.pone.0340307.t001

Stage 2: Identifying relevant studies

Relevant studies on the barriers and facilitators of TB treatment adherence will be sourced from the following electronic databases: PubMed, Scopus, Google scholar The detailed search strategy is outlined in Search Strategy Fig 1a PRISMA-ScR flow diagram. The grey literature will also be reviewed for relevant studies. To ensure “in-depth and broad” retrieval of relevant literature [22] Additionally, reference lists of included studies will be manually reviewed to identify any further relevant literature.

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Fig 1. PRISMA-ScR flow diagram illustrating the selection of studies included in the scoping review.

https://doi.org/10.1371/journal.pone.0340307.g001

Eligibility criteria

Studies eligible for inclusion must meet the criteria outlined in Table 2.

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Table 2. Inclusion and exclusion criteria.

https://doi.org/10.1371/journal.pone.0340307.t002

Stage 3: Study selection

The selection of studies will be summarized using a PRISMA – ScR Study selection flow diagram (Fig 1). The researchers will pilot the search strategy to evaluate its relevance to the selected electronic databases and keywords for the study. To enhance the search comprehensiveness, thematic search terms will be combined using Boolean operators, and Medical Subject Headings (MeSH) will be applied and adjusted as needed for each database (S1 Table). The principal investigator will oversee title screening, while two independent reviewers will conduct abstract screening. Full-text screening will also be done independently based on the eligibility criteria. In cases of disagreement between the reviewers, a third reviewer will be used if any disagreements on study selection occur. Furthermore, any disagreements will first lead to a discussion between the two reviewers, during which each reviewer will explain their rationale for inclusion or exclusion based on the predefined eligibility criteria. If the reviewers are unable to reach consensus after discussion, the disagreement will be referred to a third reviewer, who will make the final inclusion decision. All excluded articles at the full-text stage will be recorded in a “Reasons for Exclusion” spreadsheet that documents the specific justification for exclusion for each study. If an article is not freely accessible online, assistance will be sought from the institution’s library services. Additionally, the original authors may be contacted via email to request full-text access if necessary. Cohen’s kappa coefficient (κ) will be calculated to assess inter-rater agreement between reviewers at the conclusion of the full-text screening phase.

Quality appraisal

To assess the quality of the studies, the Mixed Method Appraisal Tool (MMAT) version 2020 will be used [24]. This tool will evaluate the study’s aim, methodology, design, participant recruitment, data collection and analysis processes, findings, discussions, and conclusions. Additionally, the authors will cross-examine the identified themes and assess their relevance to the research question, considering the findings’ meanings and their implications for future research. While it is not typical to include quality appraisal in a systematic review, the authors have decided to include quality appraisal to enhance the interpretability and usefulness of our findings.

Stage 4: Charting the data

Two independent reviewers will extract relevant data from the full-text articles after thorough reading. A hybrid approach, combining both inductive and deductive methods, will guide the data extraction process. The form as shown in S2 Table will capture the following details: (1) author and year of publication, (2) title of study, (3) aims and objectives, (4) country of study, (5) study design, (6) study participants, (7) study results, (8) findings related to the research question, (9) conclusion, and (10) recommendations. The form will be continuously updated to ensure all relevant data are captured to address the review question effectively. If any information is missing then it will be cataloged as not stated under the appropriate column in the data extraction form.

Stage 5: Collating, summarizing and reporting the results

We will employ thematic content analysis to identify and describe patterns relevant to the research question. This process will begin with initial coding and categorization of extracted qualitative data, followed by iterative refinement to develop key themes. Specifically, we will focus on themes related to barriers and facilitators of TB treatment adherence among nomadic populations in Sub-Saharan Africa. Coding will be conducted independently by multiple reviewers, and discrepancies will be resolved through discussion to ensure rigor and consistency.

Themes will be organized into higher-level categories that reflect structural, cultural, and health-system factors influencing adherence. Findings will be presented using summary tables, thematic maps, and narrative synthesis, highlighting relationships between themes and their contextual relevance. Where possible, illustrative quotes from primary studies will be included to enrich interpretation.

In line with scoping review methodology, our synthesis will aim to map the breadth and nature of evidence rather than assess effect sizes. However, if sufficient quantitative data are available, we will consider presenting descriptive statistics (e.g., frequencies, proportions) to summarize the distribution of barriers and facilitators across contexts. This may include tables and charts showing the prevalence of specific themes by country, population subgroup, or intervention type.

Stage 6: Consultation

An experienced TB researcher will provide expert guidance throughout all the stages of the review, including in the planning, execution, and dissemination phases.

Ethics statement

This scoping review will be conducted using previously published literature and does not involve human or animal participants. Ethical approval is not required.