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The value of informal care in the context of option B+ in Malawi: a contingent valuation approach

  • Levison Stanely Chiwaula1Email author,
  • Gowokani Chijere Chirwa1,
  • Fabian Caltado2,
  • Atupele Kapito-Tembo3,
  • Mina C. Hosseinipour4,
  • Monique van Lettow2,
  • Hannock Tweya5,
  • Virginia Kayoyo4,
  • Blessings Khangamwa-Kaunda3,
  • Florence Kasende2,
  • Clement Trapence5,
  • Salem Gugsa5,
  • Nora E. Rosenberg4,
  • Michael Eliya6,
  • Sam Phiri5 and
  • For PURE Malawi Consortium
BMC Health Services ResearchBMC series – open, inclusive and trusted201616:136

https://doi.org/10.1186/s12913-016-1381-y

Received: 6 September 2015

Accepted: 12 April 2016

Published: 19 April 2016

The Erratum to this article has been published in BMC Health Services Research 2017 17:191

Abstract

Background

Informal care, the health care provided by the patient’s social network is important in low income settings although its monetary value is rarely estimated. The lack of estimates of the value of informal care has led to its omission in economic evaluations but this can result in incorrect decisions about cost effectiveness of an intervention. We explore the use of contingent valuation methods of willingness to pay (WTP) and willingness to accept (WTA) to estimate the value of informal care provided to HIV infected women that are accessing antiretroviral therapy (ART) under the Option B+ approach to prevention of mother-to-child transmission (PMTCT) of HIV in Malawi.

Methods

We collected cross sectional data from 93 caregivers of women that received ART care from six health facilities in Malawi. Caregivers of women that reported for ART care on the survey day and consented to participate in the survey were included until the targeted sample size for the facility was reached. We estimated the value of informal care by using the willingness to accept (WTA) and willingness to pay (WTP) approaches. Medians were used to summarize the values and these were compared by the Wilcoxon signed-rank test.

Results

The median WTA to provide informal care in a month was US$30 and the median WTP for informal care was US$13 and the two were statistically different (p < 0.000). Median WTP was higher in the urban areas than in the rural areas (US$21 vs. US$13, p < 0.001) and for caregivers from households from higher wealth quintile than in the lower quintile (US$15 vs. US$13, p < 0.0462).

Conclusion

Informal caregivers place substantial value on informal care giving. In low income settings where most caregivers are not formally employed, WTP and WTA approaches can be used to value informal care.

Clinical trial number

NCT02005835.

Keywords

Informal care Willingness to Pay Willingness to Accept PMTCT Option B+ Malawi

Background

Informal care is the health care that is provided by family, friends, acquaintances, or neighbours of a patient for which they do not have to be financially compensated [1, 2]. The time contributed by informal caregivers to provide care reflects a cost in the form of forgone income or forgone leisure because care is mostly provided out of obligation [2]. Unfortunately, information on the cost of providing informal care to people living with HIV (PLHIV) in Africa is not readily available and there are many calls for the generation of this information for probable integration of it in economic evaluations of healthcare interventions adopting the societal perspective [35]. Available informal care costing studies are either conducted for diseases different from AIDS or in regions outside Africa [68]. Lack of such studies in Africa may be due to methodological challenges. Most methodological papers were developed in high income countries [5, 711] using methods that cannot be directly utilized in low income settings. Revealed preference methods of opportunity cost and proxy good methods are the commonly used approaches to value informal care. The opportunity cost method values informal care time by using the market wage of the caregiver while the proxy good method values informal care time by using the market price of a close substitute [3]. Application of the revealed preference methods are challenging in low income countries because of the problems with measurement of time and its valuation. Measurement of time is problematic because the concept of time in low income countries can be slightly different to that in Europe or America. Concept of time in subsistence societies such as in Africa is attached to changes in nature such as cock crow, sun rise, midday meal, etc. and not necessarily hours and minutes [12, 13]. Other problems of the commonly used methods of measuring time are highlighted elsewhere [3, 7]. Valuation of informal care time by using wage rates is challenging in low income countries because a substantial proportion of caregivers are subsistence producers and therefore don’t receive a market wage [6]. Additionally, opportunity cost method and the proxy good method may neglect the full impact of providing informal care on the caregiver. Providing informal care involves burden, morbidity risks and in some cases even mortality risks [3, 14, 15].

We therefore attempt to estimate the cost of providing informal care to women that have been enrolled on antiretroviral therapy (ART) within Option B+ approach of the prevention of mother-to-child transmission (PMTCT) in Malawi. Option B+ is a public health approach to promote maternal health and eliminate paediatric HIV infections through a “test and treat” strategy [16, 17]. The strategy offers all HIV-infected pregnant and breastfeeding women lifelong ART regardless of CD4 count or World Health Organisation (WHO) clinical stage [16, 17]. This enables more women that have not developed AIDS symptoms to start receiving antiretrovirals (ARVs). Malawi adopted the ‘Option B+’ in 2011 following the 2010 WHO guidelines. Valuing informal care is important in this population because it involves people who would primarily be caregivers themselves and it would good it assess if they receive care when they are in need. We used the willingness to pay approach to estimate the cost as a way of dealing with the problem of unobserved market wages.

Methods

In this study, we used a modified diary that divided a day into a number of natural changes such as waking up, sunrise, main meals, sunset and sleeping. Respondents were required to indicate the activities they carried out according to the approximate time of day [6, 18].

Contingent valuation approach to informal care valuation

The paper used stated preference methods of contingent valuation method (CVM) to elicit values of informal care to overcome the challenges of using revealed preference methods in valuation of informal care in low income countries. CVM is a survey-based, hypothetical and indirect method of determining the monetary valuations associated with the provision of goods and services [19] by eliciting willingness to pay (WTP) or willingness to accept (WTA) a good or service by its users. The methods involve asking the caregivers about the minimum amount of money they would be willing to receive if they are to provide an additional amount of care [3] or the maximum amount of money they are willing to pay for somebody to provide care. In this study, WTA was elicited by asking the caregivers the question:

Suppose there is a possibility for you to provide care to somebody you are not related to for one month and the government is willing to pay you for the care you will provide. What is the minimum amount of money you would be willing to accept to provide the care?

The WTP was elicited by asking the caregivers the question:

Suppose you become too busy to provide care to your recipient and you have found somebody who is willing to be paid for him/her to provide care to your client, what is the maximum amount of money you would be willing to pay the individual per month?

WTA questions were directed to a stranger because caregivers are mostly unwillingness to associate caregiving with problems as this will culturally be considered as a sign of insufficient love or not wishing the patient [14]. When asked to attach a value to additional care they provide to their loved ones, caregivers may give protest responses.

Setting and study sites

This study was implemented as part of the formative research of PMTCT Uptake and REtention (PURE) Clinical trial in Malawi. The PURE trial was one of the six trials supported by the Department of Foreign Affairs, Trade and Development Canada (DFADT) through World Health Organisation—Integrating and Scaling up PMTCT though Implementation Research (INSPIRE) Projects [20]. The trial was designed to evaluate facility-based and community-based support models of providing PMTCT care to strengthen uptake and retention of mothers and families in PMTCT care in Malawi. The overall trial hypothesis is that enhanced support for women and their families within facilities and/or through community outreach will result in improved retention in the continuum of PMTCT care [21]. The aims of the formative research for the PURE trial were to collect baseline information about the provision of PMTCT services; help to define the nature and scope of each intervention arm; and serve as a baseline for the qualitative and economics components of the trial.

The study was conducted in three health zones of Malawi, namely South East, South West and Central West zones. The six health facilities were purposively selected from a list of 21 facilities that qualified to be in PURE trial [21]. The six facilities were selected based on their variability in geographical location, level of service provision, ownership, and size of the facility.

Study design and data collection

We purposively decided to collect data from 15 care recipients and their care givers per health facility. The study involved six health facilities that were purposively selected from a list of 21 facilities that qualified for inclusion in the trial [21]. At each health facility, health care workers identified women that were enrolled in Option B+. All identified women were requested to participate in the study until the sample size was reached. Women who consented to participate in the study were interviewed and asked to identify their primary caregivers that were also interviewed. We targeted primary caregivers only because we assumed that these are the individuals that provided most of the informal care. Data was collected using a semi structured questionnaire between March and April 2013 through face to face interviews. The final sample size was 93 (Table 1 and Additional file 1).
Table 1

Summary health facilities and sample sizes

Name of Facility

Health Zone (Location)

Level of Service

Ownership

Location

Sample Size

Mulanje DH

South East

Secondary

Public

Rural

15

Muloza HC

South East

Primary

Public

Rural

16

Nsipe HC

Central West

Primary

CHAM

Rural

15

Lobi RH

Central West

Primary

Public

Rural

16

Trinity MH

South West

Secondary

CHAM

Rural

15

Makhetha HC

South West

Primary

Public

Urban

16

Note: DH District Hospital, HC Health Centre, RH Rural Hospital, MH Mission Hospital

Statistical analysis

Data analysis involved determination of household socioeconomic status and assessment of the health related quality of life (HRQoL) of PLHIV and their caregivers, and the assessment of the relationship between socioeconomic status and health outcomes with the value of informal care. Household socioeconomic status was derived by using an asset index that was derived by using the multiple correspondence analysis [22]. The households were categorized into two groups depending on their position on the wealth status. EQ5D was used to measure the HRQoL. The EQ5D assesses health status on five domains of mobility, self-care, usual activities, pain/discomfort and anxiety/depression at three levels which include no problem, some problems, and extreme problems/unable to perform task [23]. Caregivers and PLHIV were considered to have a perfect health state if they reported to have no problems with all the five domains of the EQ5D and imperfect if they reported a problem in at least one of the domains. We used descriptive statistics of medians and interquartile range (IQR) to analyse the data because our sample is small. The differences in the medians were tested by using the Wilcoxon signed-rank test. Data analysis was conducted in Stata version 13.

Results

Characteristics of informal caregivers

The descriptive characteristics of the informal caregivers and informal care recipients w presented in Table 2. Participation rate was 93/93(100 %) for both patients and guardians. The findings show that most of the informal caregivers were male and the majority of them were husbands of care recipients. Care giving was also provided by mothers, siblings, in laws and other family members or neighbours. The median age of informal caregivers was 38 years and that of care recipients was 28 year. Most of caregivers 69/93(74 %) and care recipients 61/93(66 %) were married. The findings also show that majority of caregivers 71/93 (79 %) and care recipients 76/93(82 %) had no or primary level education. Most of the caregivers and care recipients obtained their incomes from farming and petty trading. The median monthly income for caregivers was MK2720 (~US$6.80).
Table 2

Characteristics of informal caregivers and care recipients

Variable

 

Informal caregiver

Informal care recipients

Characteristic

n

Statistic

n

Statistic

Sex (%)

Male

66

71

0

0

 

Female

27

29

93

100

Relationship with care recipient

    
 

Husband (%)

49

53

  
 

Mother

14

15

  
 

Daughter

3

3

  
 

Sibling

9

10

  
 

In law

10

11

  
 

Other

8

9

  

Age

Median (IQR)

93

38 (32,51)

93

28(23, 31)

Marital Status (%)

    
 

Married

69

74

61

66

 

Widowed

14

15

9

10

 

Separated

10

11

20

21

 

Never Married

0

0

3

3

Level of Education (%)

    
 

None

14

15

7

8

 

Primary

59

64

69

74

 

Secondary

19

20

16

17

 

Post-secondary

1

1

1

1

Major Source of Income (%)

    
 

Permanent employee

8

9

0

0

 

Temporary employee

11

12

1

1

 

Farmer

32

34

26

28

 

Small businesses

30

32

38

41

 

Casual work

8

9

16

17

 

Other

3

3

12

13

Monthly income (Median)

93

-

93

2720 (1000, 5000)

Amount of informal care time

Although all the 93 informal caregivers were identified by the women receiving care, only 56 % (52/93) of them were involved in activities that were defined as informal care in this study: collecting drugs for the patient, escorting the patient to the health facility, providing encouragement and counselling to the patient. Other activities such as washing clothes, preparing meals, and collecting water were not defined as informal care in this study because some of these are done to other members of the family even in the absence of HIV infection. The median values of informal care are thus provided for caregivers that reported to have supplied positive informal care hours. Data on informal caregiving activities and time is presented in Table 3.
Table 3

Median of informal care time provided to women on Option B+ in month

Informal care activity

Frequency

Percent

Median (IQR)

Mean (Std Dev)

Collecting drugs for the women

1

1.1

0.0 (0.0, 0.0)

0.0 (0.0)

Escorting the women to health facility

3

3.2

0.0 (0.0, 0.0)

0.7(5.1)

Providing encouragement to the women

52

55.9

0.8 (0.0, 16.0)

17.2(34.2)

Total informal care time

52

55.9

0.8 (0.0, 16.0)

17.9 (37.5)

The median informal care time was about 0.8 h in a month while the mean was 18 h. Most of informal care provided to women on Option B+ was in the form of encouragement to the mothers.

WTP and WTA

The estimated median WTA to provide informal care was US$30.0 (US$13.8, US$50.0) while the median WTA for informal care was US$12.5 (US$7.5, US$25.0)) and the two were statistically different (p < 0.000). These were also estimated for different sub-groups of informal carers and the results are presented in Table 4.
Table 4

Median values of willingness to accept and willingness to pay for informal care (US$ per month)

Characteristics

Frequency

Willingness to Accept

Willingness to Pay

Male

66

38

13

Female

27

30

13

p-value

 

0.218

0.1682

Rural

77

25

13

Urban

16

50

21

p-value

 

0.0320

0.0001

Care Recipient in Perfect HRQoL

48

30

13

Care recipient in Imperfect HRQoL

45

34

13

p-value

 

0.5613

0.8713

Carer in Perfect HRQoL state

56

28

13

Carer in Imperfect HRQoL state

27

38

13

p-value

 

0.9551

0.8430

Lower socioeconomic status

47

25

13

Higher socioeconomic status

46

38

15

p-value

 

0.0932

0.0462

All Observations

93

30 (17.5, 56.3)

12.5(7.5,25)**

Note: ** p-value for difference between WTA and WTP = 0.000Exchange rate at time of survey: 1 USD = MK400

The median WTA was larger than the median WTP for the different caregiver sub-groups. The median WTP for most of the caregiver sub-groups was around US$13 while the median WTA for different caregiver sub-groups varied between US$25 and US$50. The median WTA and WTP for informal care for caregivers from urban areas and caregivers in the higher wealth quintile are were larger than the for caregivers from the rural areas and in the lower wealth quintiles, respectively. There was no difference in the WTA and WTP for male and female caregivers.

Discussion

We estimated informal care time and value provided to women receiving ARVs under Option B+ in Malawi. In our sample most of the caregivers are husbands of the care recipients. This makes our sample different from other studies that have shown that women are principal providers of informal care [2, 18] because they are culturally expected to do so. This finding suggests that when women, who are culturally principal informal caregivers are in need of care, husbands are the likely providers of informal care

We also found that 66 % were self-employed through faming or businesses. This creates flexibility on the caregivers to allocate time to informal care giving. However, the high proportion of self-employed caregivers also creates problems in determining the wage rates when we are using the opportunity cost method of valuing informal care, thereby supporting the approaches we used.

The median value of informal care provided to women in PMTCT under the Option B+ is US$13 per month when we use the willingness to pay approach and US$30 per month when we use the willingness to accept approach. The observed difference in the median values of informal care estimated by the WTA and WTP is not unique to our study. Studies that have estimated both WTA and WTP for health services in general [22, 23] and for informal care [11] have also established this pattern. We however note that the magnitude in the differences may also be influenced by the use of different reference care recipients in the questions—loved one for WTP and stranger for WTA. In responding to willingness to pay questions, caregivers consider their income generation opportunities. The informal care value that has been derived through the WTA approach may be biased upwards because they reflect a potential income to the caregivers. We therefore considered the value derived from WTP to be more realistic. Other studies have also placed more weight on WTP [23].

The estimated values of informal care are comparable with values derived in other studies although the settings and diseases are different. For example, Ama and Seloilwe [18] in Botswana estimated the value of informal care time for people living with HIV and AIDS at US$25 per month while Van den Berg et al. [11] used the WTP and WTA approaches to estimate the value of informal care to be between €7(~US$6.27) and €11 (~US$9.86) per month. Our view is that provision of informal care is obligatory in African context such that caregivers would provide care because society is expecting them to do so [2]. The obligatory nature of care giving implies that caregivers would have been working in productive activities or enjoying leisure had they not provided informal care. The estimated values of informal care are also substantially higher than the monthly median incomes of care recipients which was estimated at US$6.80. The estimates we found are therefore suggesting that caregivers forgo a substantial amount of income in form of productive time and leisure. These estimates suggest that inclusion and exclusion of informal care in cost effectiveness analyses of PMTCT programmes in general and Option B+ in particular would result in different conclusions.

Caregivers from urban centres and those from higher wealth quintile had higher values of informal care than those from rural areas and lower wealth quintile. Using regression analysis, van den Berg et al. [11] also found high values of informal care for high income households. High values of informal care for urban dwellers and households in high socioeconomic groups reflect the high ability to pay for those households. This is consistent with economic theory because we expect the individuals from high income families to have high opportunity cost of time. The health related quality of life of the care recipient and the caregiver has not been observed to significantly relate to the elicited values of informal care.

The results in this study seem to be within the ranges of other informal care valuation studies. However, we are not confident to strictly compare our findings with these estimates because the settings and contexts are not similar. This is due to the fact that there aren’t many studies that have valued informal care for similar populations and in similar settings.

Conclusions

Informal caregivers of women that are receiving ARVs under the Option B+ bears cost in the form of forgone productive time and leisure. In low income settings where formal employment is rare, these can be estimated by using willingness to pay or willingness to accept approaches. The estimated values should be considered in cost effectiveness analysis of PMTCT programmes because their exclusion may result in misleading conclusions..

Ethics

Ethical approval for the research was obtained from the Malawi’s National Health Sciences Research Committee (NHSRC), the University of North Carolina Institutional Review Board, WHO Ethics Review Committee and the University of Toronto Institutional Review Board.

Consent to participate

Survey participants provided written informed consent.

Availability of data and materials

Data that are supporting our findings have been made available as an Additional file.

Notes

Abbreviations

ART: 

antiretroviral therapy

ARVs: 

antiretrovirals

CVM: 

contingent valuation method

DFADT: 

Department of Foreign Affairs, Trade and Development Canada

HRQoL: 

health related quality of life

INSPIRE: 

INtegrating and Scaling up PMTCT though Implementation Research

IQR: 

interquartile range

NHSRC: 

National Health Sciences Research Committee

PLHIV: 

people living with HIV

PMTCT: 

prevention of mother-to-child transmission

PURE: 

PMTCT Uptake and REtention

WHO: 

World Health Organisation

WTA: 

willingness to accept

WTP: 

willingness to pay

Declarations

Acknowledgments

We acknowledge the financial and technical support by the World Health Organisation and Canada’s Department of Foreign Affairs, Trade and Development (DFATD) through the INSPIRE projects. We are also grateful to all study participants for their participation and to all clinic and intervention staff for their dedicated contributions to the PURE Clinical trial.

Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.

Authors’ Affiliations

(1)
Department of Economics, University of Malawi
(2)
Dignitas International
(3)
College of Medicine, University of Malawi
(4)
University of North Carolina Project
(5)
Lighthouse Trust
(6)
Department of HIV/AIDS, Ministry of Health

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Copyright

© Chiwaula et al. 2016