MR Microinsurance_2012_03_29.indd - International Labour ...

164 Health insurance
Table 7.3 Association between income and WTP
Authors Income proxy used WTP (% of income proxy) Trend 1
Authors Income proxy used WTP (% of income proxy) Trend
Walraven Weekly expenditure per adult
equivalent
3.20 NS
Asenso-Okyere et al. Self-reported income (HH survey) 1.9 rural and 2.5 urban Up
Mathiyazhagan 3 categories: low, middle and high
(unspecifi ed criteria)
n.a. Up
Masud et al. Socio-economic score & income 3.0 (only those where WTP>0) Up
Dong et al. Consumption/expenditure 2.15 (calculated) Up
Binam et al. Income of respondent 2.54 (assumed average income) Up
Asgary et al. “Wealth and income variable”
based on assets
1.4 (assumed average income) n.s.
Asfaw and Braun Annual farm and non-farm income 1.4 (calculated) Up
Bärnighausen et al. Self-reported income (HH survey) 4.6, 7.8, 6.8, 6.9 (4 packages) Up
Ying et al. Self-reported income (HH survey) 1.4, 2.0, 2.2 (3 packages) Up
Dror et al. Self-reported income (HH survey) 1.35 income, 1.8 expenditure (median) Up
Lofgren et al. 2 categories: poor/rich households
(determined by local leaders).
n.a. Up
Gustafsson-Wright et al. Consumption/expenditure 2.25 Up
Onwujekwe et al. SES index, based on assets n.a. Up
1
Walraven Weekly expenditure per adult
equivalent
3.20 NS
Asenso-Okyere et al. Self-reported income (HH survey) 1.9 rural and 2.5 urban Up
Mathiyazhagan 3 categories: low, middle and high
(unspecifi ed criteria)
n.a. Up
Masud et al. Socio-economic score & income 3.0 (only those where WTP>0) Up
Dong et al. Consumption/expenditure 2.15 (calculated) Up
Binam et al. Income of respondent 2.54 (assumed average income) Up
Asgary et al. “Wealth and income variable”
based on assets
1.4 (assumed average income) n.s.
Asfaw and Braun Annual farm and non-farm income 1.4 (calculated) Up
Bärnighausen et al. Self-reported income (HH survey) 4.6, 7.8, 6.8, 6.9 (4 packages) Up
Ying et al. Self-reported income (HH survey) 1.4, 2.0, 2.2 (3 packages) Up
Dror et al. Self-reported income (HH survey) 1.35 income, 1.8 expenditure (median) Up
Lofgren et al. 2 categories: poor/rich households
(determined by local leaders).
n.a. Up
Gustafsson-Wright et al. Consumption/expenditure 2.25 Up
Onwujekwe et al. SES index, based on assets n.a. Up
1 Up = WTP increases with income, n.s. = not signifi cant.
It must be emphasized at the outset that estimation of income in our context is
rendered very complex and unreliable by the cumulative eff ect of 1) there being only
partial records (or none at all) of income for households working in the informal
economy, which represent the majority of the poor in low-income countries; 2) an
endemic and persistent irregularity in income fl ows due to seasonal fl uctuations and
the erratic employment patterns of day-labourers and self-employed people in agriculture
or family businesses; and 3) widespread inaccuracy in self-reported income,
due to confusion regarding the monetary value of non-monetary income.
As could be expected, diff erent researchers used diff erent methods to obtain
income proxy. A commonly used method is self-reported income, obtained
through a survey. Since there could be many sources of income at household
level, it is unlikely to obtain a reliable estimate in answer to a direct question
such as “What is the income of the household?”. Th erefore, most surveyors use a
series of questions, but there is no uniform standard for them.
Asenso-Okyere et al. (1997), Asfaw and Braun (2005), Bärnighausen et al.
(2007), Ying et al. (2007), Masud et al. (2003) and Dror et al. (2007) reported that
they had obtained household or personal income information through surveys.
Expenditure/consumption information is often used because it is considered
more reliable than income information in developing countries. WHO uses this data,
and many low- and middle-income governments, in offi cial surveys, collect information
on consumption/expenditure rather than on income (e.g. the Indian National
Sample Survey Organization). Masud et al. (2003), in addition to income, created a