Hi, I am Rick Davies, an Evaluation consultant, based in Cambridge, UK. The Basic Necessities Survey (BNS) is a method of measuring poverty that is:
- Simple to design and implement. The results are easy to analyse and to communicate to others
- Democratic in the way that it identifies what constitutes poverty and who is poor
- Rights-based, in its emphasis on entitlement
The BNS builds on and adapts earlier methods that have been used to measure poverty by measuring deprivation and which emphasise the “consensual” definition of poverty. However, the BNS is innovative in the way in which (a) individual poverty scores and (b) a poverty line are generated from respondents’ survey responses.
The BNS examines two aspects of people’s lives: (a) their material conditions, (b) their perceptions of these material conditions. Both have consequences for the quality of people’s lives.
Basic necessities are democratically defined as those items listed in a “menu” that 50% or more of respondents agree “are basic necessities that everyone should be able to have and nobody should have to go without”. Items are weighted for importance according to the percentage of respondents who say an item is a basic necessity (between 50% and 100%). Respondents’ poverty (BNS) scores are based on the sum of the weightings of the basic necessities they have, as a percentage of the total they could have if they had all basic necessities. Items for inclusion in a BNS menu are identified through prior stakeholder consultations and include things, activities and services that can be reliably observed.
The BNS has been widely used and adapted particularly by international conservation NGOs who want to monitor and evaluate the impact of their work. Most notably by the Wildlife Conservation Society and supported by USAID.
Possible concerns:
- Do different sections of the community have different views about what things are basic necessities? For example, women may have different views to men? Surveys in the UK, Vietnam and South Africa show high levels of agreement across genders.
- Do people’s views of what are basic necessities reflect their bounded realities? If they don’t know how others live, how can they have such expectations? In the UK and South Africa, the expectations of poorest respondents were not significantly different from those of the richer respondents
- Do people limit their view of what are necessities when they can’t achieve them? In South Africa “…there is very little evidence of people reporting that they had chosen not to possess any of the socially perceived necessities”
Lessons Learned:
- Repeat surveys can show long term trends. The 2006 Basic Necessities Survey (BNS) in Can Loc District, Ha Tinh Province, Vietnam, includes comparisons with households surveyed in 1997
Hot Tip:
- Where to go to first, to learn more: The Basic Necessities Survey webpage on MandE NEWS website provides detailed information on survey design and analyses, and extensive references to its use and related work.
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Thanks for sharing this, Rick! It is very helpful. I’m also enjoying the discussion the other side as I’m presently in a study for a formative nutrition assessment and I thought this BNS would have some learning points for the study.