Table 5.

Framework for the integration of innovative qualitative methods into randomised controlled trials of complex health interventions

Categories adapted from CONSORT	Methodological Challenge	Threats to design or results	Type of bias	Validity affected	Qualitative research solution	Examples of qualitative methods
Background and setting	Ensure relevance of the problem to the context	Affects applicability, acceptability, sustainability and transferability of potential positive findings	N/A	External	To identify social, cultural, health, economic or political factors that might affect uptake and sustainability of positive results	Direct observation, ideally in-depth but if time or resources are limited, as part of a rapid ethnographic appraisal or Broad Brush Survey
	Obtain buy-in from stakeholders	Reduces translation and sustainability of results into changes in policy and practices	N/A	External	To overcome potential barriers to implementation and promote uptake of intervention	In-depth interviews with policymakers and stakeholders | Document analysis
Intervention design and compliance	Ensure cultural acceptability and practical feasibility of the intervention	Impacts adherence and increases number of drop-outs	Adherence Withdrawal	Internal	To tailor intervention in order to increase retention and adherence	Diary methods – via Interactive voice responses or SMS
Recruitment and enrolment	Guarantee representativeness of the sample and efficient recruitment methods	Risks achieving the required sample size to detect significant effect	Selection	Internal External	To determine the best possible recruitment method to reach target population	Community mapping | Spiral walks
Randomization and allocation	Guarantee balanced randomization	Reduces comparability between groups	Selection Confounding	Internal External	To identify contextual factors that can affect the effect of the intervention and reduce comparability between groups	Observation | Public randomization
Participant follow-up	Minimize the number of participants leaving the study	Enables unequal loss of participants between groups which can affect causal inference	Attrition Confounding (if differential attrition between trial arms)	Internal External	To prevent or understand reasons for loss to follow-up and improve retention strategies	Diary methods, mobile-based methods such as interactive voice response on SMS / WhatsApp | peer support for adherence
	Improve adherence to the intervention	Modifies the magnitude/direction of effect	Adherence	Internal	To understand reasons for non-adherence to the intervention
Data collection	Enhance reliability and quality of data	Allows inconsistent or unreliable measurements which can affect the observed magnitude and direction of the effect	Instrument	Internal	To avoid or identify errors in the measurement and data collection process.	Co-designing measurement tools with participants | Qualitative tool validation
	Maintain objectivity during the data collection process	Threatens the validity of the data collected and/or measured to answer the objective	Instrument Recall Social desirability	Internal	To assess and validate the process of data collection.	FGD with prompts such as flashcards or images Pair interviews and role playing
Analysis and results	Identify the mechanisms underpinning the effect of the intervention	Limits an informed discussion of the results (negative or positive)	N/A	External	To triangulate the quantitative findings and identify contextual information that may have affected the results	Participatory Analysis methods

Abbreviations: CONSORT Consolidated Standards of Reporting Trials, N/A not applicable, SMS short message service.