Box 20.3.a: Directly observed therapy and tuberculosis: a synthesis of qualitative evidence –  summary

Background: DOT is part of a World Health Organization (WHO)-branded package of interventions to improve the management of TB and adherence with treatment (Maher 1999). DOT involves asking people with TB to visit a health worker, or other appointed person, to receive and be observed taking a dose of medication. A Cochrane Intervention review of trials of DOT showed conflicting evidence as to the effects of DOT when compared with self-administration of therapy. To supplement this review, we conducted a synthesis of qualitative evidence concerning people with, or at risk of, TB, service providers and policy makers, to explore their experience and perceptions of TB and treatment. Findings were used to help explain and interpret the Cochrane Intervention review and to consider implications for research, policy and practice.

Review questions: Two broad research questions were addressed:

  1. What are the facilitators and barriers to accessing and complying with tuberculosis treatment?

  2. Can exploration of qualitative studies and/ or qualitative components of the studies included in the intervention review explain the heterogeneity of findings?

Method:

Search methods: A systematic search of the wider English-language literature was undertaken: The following terms were used: DOT; DOTS; Directly observed therapy; Directly observed treatment; supervised swallowing; self-supervis*; in combination with TB and tuberculosis. We experimented with using methodological filters by including terms such as ‘qualitative’, but found this approach unhelpful as the Medline MeSH heading ‘Qualitative Research’ was only introduced in 2003, and even after 2003 many papers were not identified appropriately as qualitative. We searched MEDLINE, CINAHL, HMIC, Embase, British Nursing Index, International Bibliography of the Social Sciences, Sociological Abstracts, SIGLE, ASSIA, Psych Info, Econ lit, Ovid, Pubmed, the London School of Hygiene and Tropical Medicine database of TB studies (courtesy of Dr Simon Lewin), and Google Scholar. Reference lists contained within published papers were also scrutinized. A network of personal contacts was also used to identify papers. All principal researchers involved in the six randomized trials included in the Cochrane Intervention review were contacted and relevant qualitative studies obtained.

Selection and appraisal of studies: The following definition was used to select studies: ‘papers whose primary focus was the experiences and/or perceptions of TB and its treatment amongst people with, or at risk of, TB and service providers’. The study had to use qualitative methods of data collection and analysis, as either a stand-alone study or a discrete part of a larger mixed-method study. To appraise methodological and theoretical dimensions of study quality, two contrasting frameworks were used independently by JN and JP (Popay 1998a, Critical Appraisal Skills Programme 2006). Studies were not excluded on quality grounds, but lower quality studies were reviewed to see if they altered the outcome of the synthesis – which they did not.

Analysis: Thematic analysis techniques were used to synthesize data from 1990-2002, and an update of literature to December 2005. Themes were identified by bringing together components of ideas, experiences and views embedded in the data – themes were constructed to form a comprehensive picture of participants’ collective experiences. A narrative summary technique was used to aid interpretation of trial results.

Findings: Fifty-eight papers derived from 53 studies were included. Five themes emerged from the 1990-2002 synthesis, including: socio-economic circumstances, material resources and individual agency; explanatory models and knowledge systems in relation to tuberculosis and its treatment; the experience of stigma and public discourses around tuberculosis; sanctions, incentives and support, and the social organization and social relationships of care. Two additional themes emerged from the 2005 update: the barriers created by programme implementation, and the challenge to the model that culturally determined factors are the central cause of treatment failure.

Conclusions: The Cochrane Intervention review did not show statistically significant differences between DOT and self-supervision, thereby suggesting that it was not DOT per se that led to an improvement in treatment outcomes. The six randomized trials tested eight variations of DOT compared with self-supervision and varied enormously in the degree to which they were tailored around the needs of people with TB. The variants of DOT differed in important ways in terms of who was being observed, where the observation took place and how often observation occurred. The synthesis of qualitative research suggests that these elements of DOT will be crucial in determining how effective a particular type of DOT will be in terms of increased cure rates. The qualitative review also highlighted the key role of social and economic factors and physical side effects of medication in shaping behaviour in relation to seeking diagnosis and adhering to treatment. More specifically, a predominantly inspectorial approach to observation is not likely to increase uptake of service or adherence with medication. Inspectorial elements may be needed in treatment packages, but when the primary focus of direct observation was inspectorial rather than supportive in nature, observation was least effective. Direct observation of an inspectorial nature had the most negative impact on those who had the most to fear from disclosure, such as disadvantaged women who experienced gender-related discrimination. In contrast, treatment packages in which the emphasis is on person-centred support are more likely to increase uptake and adherence. Qualitative evidence also provided some insights into the type of support that people with TB find most helpful. Primarily, the ability of the observer to add value depended on the observer and the service being able to adapt to the widely-varying individual circumstances of the person being observed (age, gender, agency, location, income, etc.). Given the heterogeneity amongst those with TB, findings support the need for locally tailored, patient-centred programmes rather than a single worldwide intervention.