How to study vulnerable groups of children?

Experiences from studies on street children and child beggars

in Mali, Ghana and SenegalAnne Hatløy, PhD

Fafo Institute for Applied International studiesNorway

Aim

• Identify street children and child beggars in capitals in West Africa

• Give an estimation of total numbers• Describe the socio-economic and

demographic characteristics of the population

The studies

DakarChild beggars

2006/07

Bamako and Accra:Street children

2004

Overview of the projects

• Bamako , Mali: July 2004 Quantification and profiling of street children Funded by Norweigian Ministry of Foreign Affaires

• Accra, Ghana: September 2004 Profiling of street children Funded by Norweigian Ministry of Foreign Affaires

• Dakar, Senegal: November 2006 Quantification and profiling of child beggars Funded by the World Bank, in collaboration with UCW

(Understanding Children’s Work)

• Dakar, Senegal: February 2007 Quantification of child beggars Funded by the World Bank, in collaboration with UCW

Children living with their families

Children in the street

Important to identify the study group

Children off the street

Choranic school children

Disabled children

Accompaning children

Child beggars

Methods

• Capture – Recapture (CR) This method has as an objective to estimate the

population for which there exists no sample frame and give representative data for this population

• Respondent Driven Sampling (RDS) This method is based on a kind of snowball sample with

a dual incentive system. It aims to give a representative sample for the study population

Capture – Recapture

• This method is normally used to obtain the size of the study population – but can also be used to characterize the population group

• The classic case is the fishes in a lake

1. A number of fishes is captured in a lake, the numbers of CAPTURED fishes are noted and they are marked by painting their tails blue, and the fishes are put back into the lake

2. In the same lake, a new number of fishes are RECAPTURED, the total number of fishes are noted, and the number of fishes with blue tails are noted

• The fewer fishes with blue tails – the larger is the population

Capture - Recapture

50 children

Capture - Recapture

Capture

20 children captured (blue)

Capture – Recapture

Recapture

20 recaptured, 9 marked blue

Mark – Capture - Recapture

Estimation

Petersen estimate: N=Total population

C=CapturedR=RecapturedM=Marked

Confidence interval:

1.96 * N (C+1)(R+1)(C-M) (C-M)

(M+1)2 (M+2)

M+1N= (C+1)*(R+1) -1^

Counting street children in Bamako in July 2004

• Walked through specific sites identified by NGOs during night-time

• Interviewed the children (CAPTURE)• Interviewed children some nights later on

the same sites (RECAPTURE)• Asked them if they had been interviewed

before

Counting child beggars in Dakar February 2007

• Walked through specific sites identified by NGOs during day-time

• Interviewed the children (CAPTURE)• Repeated the same the following day – asked if they have

been interviewed in the previous day (RECAPTURE)

Sample sizes and estimates of total population

Capture Recapture BothEstimatednumber Lower CI Upper CI

Bamako Jul 04

146 130 59 322 276 367

Dakar Feb 07

3,512 4,028 1,927 7,549 7,386 7,718

Respondent Driven Sampling

• Study of hidden population• Used when a sampling frame is difficult to

establish• Based on the premise that peers are better

able than outreach workers or researchers to locate and recruit other members of a hidden population

• Network-based method

Respondent Driven Sampling II

• Start with a small number of peers recruited by the reasearch team (seeds)

• Expands through successive waves of per recruitment

• Dual incentive system: The children were rewarded for the initial interview and for recruiting their friends

• Does not depend on random seeds• Does not depend on equal inclusion

probabilities

RDS in Bamako and Accra

• Started with 6-10 street children (in Accra repeated on four different sites)

• Asked them to meet at a specific point in town

• Gave them six tickets to recruit six other street children

RDS in Dakar

• Chose central sites (indoors) in the different department of Dakar region

• Started with three seeds• Asked each seed to recruit three new

peers

Profile of the children

StudyAge

(median)Boys (%)

Strangers (%)

Daily income (median USD)

Orphans (%)

Bamakon=217 14 96% 20% 1.0 USD 9%

Accran=1,341

15 25% 0% 1.1 USD 2%

Dakarn=1,624

10 97% 43% 0.9 USD 3%

It is possible to collect data on street children and child beggars