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Do material incentives improve patient adherence in tuberculosis?

Adherence to treatment for tuberculosis (TB) is frequently sub-optimal. However, good adherence is important for successful treatment and to minimize the risk of drug resistance. Adherence is also essential for different components of TB prophylaxis. Material incentives for patients to encourage them to take their treatment as prescribed, or to assist them in overcoming financial barriers to treatment, have been suggested as interventions to improve TB treatment adherence.

 Key messages

 

  • Sustained material incentives may lead to little or no difference in cure or completion of treatment for active TB, compared to no incentive

  • It is not clear if sustained material incentives improve completion of TB prophylaxis, compared to no incentive, because findings varied across studies

  • A single, once only incentive may increase the number of people who return to a clinic for reading of their tuberculin skin test, compared to no incentive

  • A single, once only incentive probably increases the number of people who return to a clinic to start or continue TB prophylaxis, compared to no incentive

  • Compared to a non cash incentive, cash incentives may slightly increase the number of people who return to a clinic for reading of their tuberculin skin test and may increase the number of people who complete TB prophylaxis

  • Compared to counselling or education interventions, material incentives may increase the number of people who return to a clinic for reading of their tuberculin skin test

  • Compared to counselling or education interventions, material incentives may lead to little or no difference in the number of people who return to a clinic to start or continue TB prophylaxis or in the number of people who complete TB prophylaxis

  • Higher cash incentives may slightly improve the number of people who return to a clinic for reading of their tuberculin skin test, compared to lower cash incentives

 

 

Adherence to treatment for tuberculosis (TB) is frequently sub-optimal. However, good adherence is important for successful treatment and to minimize the risk of drug resistance. Adherence is also essential for different components of TB prophylaxis. Material incentives for patients to encourage them to take their treatment as prescribed, or to assist them in overcoming financial barriers to treatment, have been suggested as interventions to improve TB treatment adherence.

 

Key messages

è Sustained material incentives may lead to little or no difference in cure or completion of treatment for active TB, compared to no incentive

è It is not clear if sustained material incentives improve completion of TB prophylaxis, compared to no incentive, because findings varied across studies

è A single, once only incentive may increase the number of people who return to a clinic for reading of their tuberculin skin test, compared to no incentive

è A single, once only incentive probably increases the number of people who return to a clinic to start or continue TB prophylaxis, compared to no incentive

è Compared to a non-cash incentive, cash incentives may slightly increase the number of people who return to a clinic for reading of their tuberculin skin test and may increase the number of people who complete TB prophylaxis

è Compared to counselling or education interventions, material incentives may increase the number of people who return to a clinic for reading of their tuberculin skin test

è Compared to counselling or education interventions, material incentives may lead to little or no difference in the number of people who return to a clinic to start or continue TB prophylaxis or in the number of people who complete TB prophylaxis

è Higher cash incentives may slightly improve the number of people who return to a clinic for reading of their tuberculin skin test, compared to lower cash incentives


Who is this summary for?

People making decisions concerning anti-tuberculosis treatment implementation.

This summary includes:

  • Key findings from research based on a systematic review
  • Considerations about the relevance of this research for low income countries

Not included:

  • Recommendations
  • Additional evidence not included in the systematic review
  • Detailed descriptions of interventions or their implementation

This summary is based on the following systematic review:

Lutge EE, Wiysonge CS, Knight SE, Sinclair D, Volmink J. Incentives and enablers to improve adherence in tuberculosis. Cochrane Database of Systematic Reviews 2015, Issue 9. Art. No.: CD007952.

What is a systematic review?

A summary of studies addressing a clearly formulated question that uses systematic and explicit methods to identify, select, and critically appraise the relevant research, and to collect and analyse data from the included studies.

SUPPORT – was an international project to support the use of policy relevant reviews and trials to inform decisions about maternal and child health in low- and middle-income countries, funded by the European Commission (FP6) and the Canadian Institutes of Health Research.

Glossary of terms used in this report

Background references on this topic

Background

In many settings, people’s adherence to drug treatment for TB is frequently sub optimal and many people also fail to return to a clinic to collect their TB test results, undermining global efforts to control the disease. Good adherence to treatment is important for successful treatment and also to minimize the risk of infection among contact persons and to reduce the development of treatment resistance. Material incentives, such as cash or vouchers, may both act as a reward for desired behaviour and help to overcome economic barriers to treatment adherence. Offering material incentives to people diagnosed with TB has therefore been suggested as an approach to improving TB treatment outcomes. However, such approaches may also entail risks, including encouraging unintended behaviours, such as people not taking medication in order to remain sick and continue to collect rewards.

How this summary was prepared

After searching widely for systematic reviews that can help inform decisions about health systems, we have selected ones that provide information that is relevant to low-income countries. The methods used to assess the reliability of the review and to make judgements about its relevance are described here

Knowing what’s not known is important

A reliable review might not find any studies from low-income countries or might not find any well-designed studies. Although that is disappointing, it is important to know what is not known as well as what is known.

A lack of evidence does not mean a lack of effects. It means the effects are uncertain. When there is a lack of evidence, consideration should be given to monitoring and evaluating the effects of intervention, if it is used.



About the systematic review underlying this summary

Review objectives: To evaluate the effects of material incentives and enablers given to people undergoing diagnostic testing for TB, or receiving drug therapy to prevent or cure TB
Type of What the review authors searched for What the review authors found
Study designs & interventions Randomised trials of any form of material inducement to return for TB test results, or adhere to or complete anti-TB preventive or curative treatment 12 randomised trials were included, assessing incentives for adherence to different stages of TB management: returning for reading of tuberculin skin test results (2 studies); clinic attendance for initiation of preventive therapy (1 study); clinic attendance for continuation of preventive therapy (2 studies); adherence to preventive treatment (5 studies); adherence to treatment for active TB (2 studies). The incentives used included cash, vouchers that could be redeemed for various products and food.
Participants

- Patients receiving curative treatment for TB

- Patients receiving preventa-tive therapy for TB

- Patients suspected of TB who are undergoing, and col-lecting results of, diagnostic tests

 

 Adolescents (11-19 years)(1 study); in-jection drug or cocaine users (4 studies); homeless or marginally housed adults (3 studies); prisoners (2 studies); and studies on the general adult population (2 studies)
Settings No restrictions South Africa (1 study), Timor Leste (1 study), USA (10 studies)
Outcomes

For treatment of active TB: cure and/or completion of treatment and/or successful treatment

For prophylaxis: cases of active TB; completion of prophylactic treatment

For diagnostics: number returning to collect test results

Also adverse events and costs

 

- Return for tuberculin skin test reading

- Completion of TB prophylaxis

- Return to clinic for continuation of treatment

- Successful TB treatment and / or completion of treatment

- Time needed to track participants who missed appointments

 
Date of most recent search: June 2015
Limitations: This is a well-conducted systematic review with only minor limitations.

Lutge EE, Wiysonge CS, Knight SE, Sinclair D, Volmink J. Incentives and enablers to improve adherence in tuberculosis. Cochrane Database of Systematic Reviews 2015, Issue 9. Art. No.: CD007952. 

For treatment of active TB: cure and/or completion of treatment and/or successful treatment

For prophylaxis: cases of active TB; completion of prophylactic treatment

For diagnostics: number returning to collect test results

Also adverse events and costs

Lutge EE, Wiysonge CS, Knight SE, Sinclair D, Volmink J. Incentives and enablers to improve adherence in tuberculosis. Cochrane Database of Systematic Reviews 2015, Issue 9. Art. No.: CD007952.

About the certainty of the 
evidence (GRADE)


High: This research provides a very good indication of the likely effect. The likelihood that the effect will be substantially different† is low.


Moderate: This research provides a good indication of the likely effect. The likelihood that effect will be substantially different† is moderate.


Low: This research provides some indication of the likely effect. Howevver, the likelihood that it will be substantially different† is high.


Very low: This research does not provide a reliable indication of the likely effect. The likelihood that the effect will be substantially different† is very high.

* This is sometimes referred to as 'quality of evidence' or 'confidence in the estimate'.

† Substantially different = a large enough difference that it might affect a decision.

See last page for more information.

Summary of findings

The review identified 12 studies, most of which were conducted among specific subgroups including teenagers, drug users, homeless persons and prisoners. Most of the studies focused on incentives to encourage people to return for reading of tuberculin skin testing and on attendance for or adherence to TB preventive therapy. Only two studies evaluated incentives for adherence to treatment for active TB.

 1) Sustained material incentives for completion of treatment for active TB

  • Sustained material incentives may lead to little or no difference in cure or completion of treatment for active TB, compared to no incentive. The certainty of this evidence is low.

Sustained material incentives compared to routine care for completion of treatment for active TB
People:  Recipients of care from TB control services
Settings:  South Africa and Timor Leste
Intervention: Material incentives, such as cash or grocery vouchers, sustained across the du-ration of treatment
Comparison: Routine care
Outcomes Absolute effect*
 Relative effect
(95% CI)

Number of
participants

(studies)		 Certainty of the evidence
(GRADE)

Without Incentives

(routine care)

 With Incentives
Cure or completion of treatment for active TB
 721 per 1000
 750 per 1000
(622 to 1000)

RR 1.04
(0.97 to 1.13)

4356

(2 studies)

Low

Margin of error = Confidence interval (95% CI)    RR:  Risk ratio     GRADE: GRADE Working Group grades of evidence (see above and last page)

* The risk WITHOUT the intervention is based on the control group of each study. The corresponding risk WITH the intervention (and the 95% confidence interval for the difference) is based on the overall relative effect (and its 95% confidence interval).

2) Material incentives for TB prophylaxis

  • A single, once only incentive may increase the number of people who return to a clinic for reading of their tuberculin skin test, compared to no incentive. The certainty of this evidence is low. 
  • A single, Once only incentive probably increases the number of people who return to a clinic to start or continue TB prophylaxis, compared to no incentive. The certainty of this evidence is moderate.
  • it is not clear if sustained material incentives improve completion of TB prophylaxis, compared to no incentive, because findings varied across studies. The certainty of this evidence is low.

Material incentives compared to routine care for TB prophylaxis
People:  Recipients of care from TB control services
Settings:  USA
Intervention: Material incentives, such as cash or grocery vouchers, on a once only basis (for tuberculin skin test reading and returning to a clinic to start or continue TB prophylaxis) or sustained across the duration of treatment (for completion of TB prophylaxis)
Comparison: Routine care
Outcomes Absolute effect*
 Relative effect
(95% CI)

Number of 
participants

(studies)		 Certainty of the evidence
(GRADE)

Without Incentives

(routine care)

 With Incentives
Cure or completion of treatment for active TB
 721 per 1000
 750 per 1000
(622 to 1000)

RR 1.04
(0.97 to 1.13)

4356

(2 studies)

Low
Return to clinic to start or continue TB prophylaxis

249 per 1000

393 per 1000

(316 to 488)

RR 1.58

(1.27 to 1.96)

595

(3 studies)

Moderate
Completion of TB prophylaxis Findings varied: 1 study reported that there may be improvement in completion of prophylaxis while 2 studies reported that incentives may make little or no difference   

Data not pooled

869

(3 studies)

Low

Margin of error = Confidence interval (95% CI)    RR:  Risk ratio     GRADE: GRADE Working Group grades of evidence (see above and last page)

* The risk WITHOUT the intervention is based on the control group of each study. The corresponding risk WITH the intervention (and the 95% confidence interval for the difference) is based on the overall relative effect (and its 95% confidence interval).

3) Cash versus non-cash incentives for TB prophylaxis

  • Compared to a non cash incentive, cash incentives may slightly increase the number of people who return to a clinic for reading of their tuberculin skin test. the certainty of this evidence is low.
  • Compared to a non-cash incentive,cash inventives may increase the number of people who complete TB prophylaxis. The certainty of this evidence is Low.

Cash versus non-cash incentives for TB prophylaxis
People:  People at high risk of developing TB
Settings:  USA
Intervention: Cash incentive
Comparison: Non cash incentive, including grocery store coupons, phone cards and bus to kens
Outcomes Absolute effect*
 Relative effect
(95% CI)

Number of 
participants

(studies)		 Certainty of the evidence
(GRADE)

Without non cash incentive

 With cash incentive
Return to clinic for tuberculin skin test reading
 841 per 1000

950 per 1000

(900 to 992)

RR 1.13

(1.07 to 1.19)

652

(1 study)

Low
Completion of TB prophylaxis

638 per 1000

804 per 1000

(651 to 995)

RR 1.26

(1.02 to 1.56)

141

(1 study)

Low
Completion of TB prophylaxis Findings varied: 1 study reported that there may be improvement in completion of prophylaxis while 2 studies reported that incentives may make little or no difference   

Data not pooled

869

(3 studies)

Low

Margin of error = Confidence interval (95% CI)    RR:  Risk ratio     GRADE: GRADE Working Group grades of evidence (see above and last page)

* The risk WITHOUT the intervention is based on the control group of each study. The corresponding risk WITH the intervention (and the 95% confidence interval for the difference) is based on the overall relative effect (and its 95% confidence interval).

4) Material incentives compared to other interventions for TB prophylaxis

  • compared to counselling or education interventions,material incentives may in crease the number of people who return to a clinic for reading of their tuberculin skin test. The certainty of this evidence is Low.
  • Compared to counselling or education interventions, material incentives may lead to little or no difference in the number of people who return to a clinic to start or continue TB prophylaxis. The certrainty of this evidence is Low.
  • Compared to counselling or education interventions, material incentives may lead to little or no difference in the number of people who complete TB prophylaxis. The certainty of this evidence is low

Material incentives compared to other interventions for TB prophylaxis
People:  People at high risk of developing TB. The studies included homeless people, people recently released from prison, drug users and adolescents
Settings:  USA
Intervention: Incentive
Comparison: Counselling or education session
Outcomes Absolute effect*
 Relative effect
(95% CI)

Number of 
participants

(studies)		 Certainty of the evidence
(GRADE)

With counselling or education session

(non incentive intervention)

With

incentive

 
Return to clinic for tuberculin skin test reading

429 per 1000

927 per 1000

(669 to 1000)

 

RR 2.16

(1.56 to 3.00)

 

1366

(2 studies)

 

Low
Return to clinic to start or continue TB prophylaxis

381 per 1000

419 per 1000

(351 to 499)

 

RR 1.10

(0.92 to 1.31)

 

535

(2 studies)

 

Low
Completion of TB prophylaxis 
 444 per 1000

462 per 1000

(262 to 813)

 

 

RR 1.04

(0.59 to 1.83)

 

837

(3 studies)

 

Low

Margin of error = Confidence interval (95% CI)    RR:  Risk ratio     GRADE: GRADE Working Group grades of evidence (see above and last page)

* The risk WITHOUT the intervention is based on the control group of each study. The corresponding risk WITH the intervention (and the 95% confidence interval for the difference) is based on the overall relative effect (and its 95% confidence interval).

5) Different levels of material incentives

  • Higher cash incentives may slightly improve the number of people who return to a clinic for reading of their tuberculin skin test, compared to lower cash incentives. The certainty of this evidence is Low.

 

Different values of cash incentives for improving patient return for tuberculin skin test reading
People:  Drug users at high risk of developing TB
Settings:  USA
Intervention: Higher cash value ($10.00)
Comparison: Lower cash value ($5.00)
Outcomes Absolute effect*
 Relative effect
(95% CI)

Number of 
participants

(studies)		 Certainty of the evidence
(GRADE)

With lower cash value incentive ($5.00)

With higher cash value

incentive ($10.00)

 

 
Return to clinic for tuberculin skin test reading

858 per 1000

927 per 1000

(867 to 995)

 

RR 1.08

(1.01 to 1.16)

 

404

(1 study)

Low

Margin of error = Confidence interval (95% CI)    RR:  Risk ratio     GRADE: GRADE Working Group grades of evidence (see above and last page)

* The risk WITHOUT the intervention is based on the control group of each study. The corresponding risk WITH the intervention (and the 95% confidence interval for the difference) is based on the overall relative effect (and its 95% confidence interval).

 

 

 

 

Relevance of the review for low-income countries

Findings Interpretation*
APPLICABILITY

Most studies were conducted in the USA, with only two conducted in low- and middle-income countries

 

  • Most studies were conducted with specific subgroups, such as homeless people, prisoners or drug users

 

 

The findings need to be applied with caution in low-income countries given the structural and qualitative differences in health systems, healthcare provision, resources and healthcare seeking behaviour

 

  • Most of the included studies focused on specific subgroups of people, such as injection drug users. The applicability of the findings to the general population is therefore not clear

 

 
EQUITY
The review did not discuss the impacts of the intervention on equity
 Material incentives could improve equity by reducing the poverty-related impacts of TB through assisting people with TB with the costs associated with diagnosis, prophylaxis and treatment and encouraging poorer people to seek care. However, implementers need to ensure that incentives are seen as helpful and can be accessed by disadvantaged groups.
ECONOMIC CONSIDERATIONS
The review found very limited evidence on the costs of providing incentives and no evidence on cost-effectiveness

Implementing material incentives on a large scale for adherence to TB treatment or prophylaxis would require considerable resources, including the costs of the incentives and the costs of putting in place mechanisms to distribute them appropriately. Such resources may not be readily available in many LIC settings

 

  • The risk of undesirable effects of incentives, such as leakage to groups not eligible to receive them, could be higher in low income countries where incentives are likely to be relatively more valuable

 
MONITORING & EVALUATION

The review found very limited evidence on the effects of material incentives on cure or completion of treatment for active TB

 

  • For tuberculin skin testing and TB prophylaxis, the certainty of the evidence in relation to incentives is moderate or low
  • There is little evidence on harms, unin-tended behaviours, costs and cost-effectiveness
  • The evidence is generally of low cer-tainty, as most of the studies were not conducted with specific subgroups rather than with general adult populations

 

 

Rigorous studies are needed in general adult populations on the effects of material incentives on cure rates or completion of treatment for active TB, on completion of TB prophylaxis and on the number of people who return to a clinic for reading of their tuberculin skin test

 

  • These studies should also examine the costs and cost effectiveness of incentives, particularly for key target groups in low bincome countries
  • Evaluations should also consider possible adverse effects of incentives as well as the role of HIV/AIDs and other chronic conditions and socioeconomic status in modifying the effects of incentives
*Judgements made by the authors of this summary, not necessarily those of the review authors, based on the findings of the review and consultation with researchers and policymakers in low-income countries. For additional details about how these judgements were made see: http://www.support-collaboration.org/summaries/methods.htm

 

Implementing material incentives on a large scale for adherence to TB treatment or prophylaxis would require considerable resources, including the costs of the incentives and the costs of putting in place mechanisms to distribute them appropriately. Such resources may not be readily available in many LIC settings 

w The risk of undesirable effects of incentives, such as leakage to groups not eligible to receive them, could be higher in low-income countries where incentives are likely to be relatively more valuable

Additional information

Related literature

Adams LV, Talbot EA, Odato K, Blunt H, Steingart KR. Interventions to improve delivery of isoniazid preventive therapy: an overview of systematic reviews. BMC infectious diseases. 2014;14:281.

 

Karumbi J, Garner P. Directly observed therapy for treating tuberculosis. Cochrane Database of Systematic Reviews 2015, Issue 5. Art. No.: CD003343.

 

Lin S, Melendez-Torres GJ. Systematic review of risk factors for nonadherence to TB treatment in immigrant populations. Trans R Soc Trop Med Hyg. 2016;110(5):268-80.

 

Liu Q, Abba K, Alejandria MM, Sinclair D, Balanag VM, Lansang MAD. Reminder systems to improve patient adherence to tuberculosis clinic appointments for diagnosis and treatment. Cochrane Database of Systematic Reviews. 2014; 11: CD006594.

 

M'Imunya JM, Kredo T, Volmink J. Patient education and counselling for pro-moting adherence to treatment for tuberculosis. Cochrane Database of System-atic Reviews. 2012; 5: CD006591.

 

Munro SA, Lewin SA, Smith HJ, Engel ME, Fretheim A, Volmink J. Patient adher-ence to tuberculosis treatment: a systematic review of qualitative research. PLoS Med. 2007;4(7):e238.

 

Sutherland K, Leatherman S, Christianson J. Paying the patient: does it work? A review of patient-targeted incentives. London, UK: The Health Foundation. 2008. Available at: http://www.health.org.uk/publication/paying-patient-does-it-work

 

WHO. Adherence to long-term therapies: evidence for action. Geneva: World Health Organization. 2003.

 

This summary was prepared by

Simon Lewin, Norwegian Institute of Public Health, Norway and Peter Steinmann, Swiss Tropical and

Public Health Institute, Switzerland.

 

Conflict of interest

None declared. For details, see: www.support-collaboration.org/summaries/coi.htm

 

Acknowledgements

This summary has been peer reviewed by: Airton Stein and Elizabeth Lutge.

 

This review should be cited as

Lutge EE, Wiysonge CS, Knight SE, Sinclair D, Volmink J. Incentives and enablers to improve adherence in tuberculosis. Cochrane Database of Systematic Reviews 2015, Issue 9. Art. No.: CD007952.

 

This summary should be cited as

Lewin S, Steinmann P. Do material incentives improve patient adherence in tu-berculosis? A SUPPORT Summary of a systematic review. April 2017. www.support-collaboration.org/summaries.htm

 

 

Keywords

evidence-informed health policy, evidence-based, systematic review, health sys-tems research, health care, low and middle-income countries, developing coun-tries, primary health care, tuberculosis, adherence, incentive

 



About certainty of evidence (GRADE)

The “certainty of the evidence” is an assessment of how good an indication the research provides of the likely effect, i.e. the likelihood that the effect will be substantially different from what the research found. By “substantially different” we mean a large enough difference that it might affect a decision. These judgements are made using the GRADE system, and are provided for each outcome. The judgements are based on the study design (randomised trials versus observational studies), factors that reduce the certainty (risk of bias, inconsistency, indirectness, imprecision, and publication bias) and factors that increase the certainty (a large effect, a dose response relationship, and plausible confounding). For each outcome, the certainty of the evidence is rated as high, moderate, low or very low using the definitions on page 3.

For more information about GRADE

SUPPORT collaborators:

The Cochrane Effective Practice and Organisation of Care Group (EPOC) is part of the Cochrane Collaboration. The Norwegian EPOC satellite supports the production of Cochrane reviews relevant to health systems in low- and middle-income countries . www.epocoslo.cochrane.org

The Evidence-Informed Policy Network (EVIPNet) is an initiative to promote the use of health research in policymaking in low- and middle-income countries. www.evipnet.org

The Alliance for Health Policy and Systems Research (HPSR) is an international collaboration that promotes the generation and use of health policy and systems research in low- and middle-income countries. www.who.int/alliance-hpsr

Norad, the Norwegian Agency for Development Cooperation, supports the Norwegian EPOC satellite and the production of SUPPORT Summaries. www.norad.no

The Effective Health Care Research Consortium is an international partnership that prepares Cochrane reviews relevant to low-income countries. www.evidence4health.org

To receive e-mail notices of new SUPPORT summaries or provide feedback on this summary, go to: www.supportsummaries.org/contact

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