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

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 [3‐5]. Available informal care costing studies are either conducted for diseases different from AIDS or in regions outside Africa [6‐8]. Lack of such studies in Africa may be due to methodological challenges. Most methodological papers were developed in high income countries [5, 7‐11] 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.

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].

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.

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..