IJE Advance Access originally published online on May 21, 2007
International Journal of Epidemiology 2007 36(4):858-864; doi:10.1093/ije/dym092
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
A field test of three LQAS designs to assess the prevalence of acute malnutrition
1Academy for Educational Development, FANTA Project, Washington DC, USA.
2The World Bank, Washington DC, USA.
3Independent Consultant, Formerly with Catholic Relief Services, Emergency Response Team, Nairobi, Kenya.
4Ohio State University, Center for Biostatistics, Columbus, Ohio, USA.
5Catholic Relief Services, Baltimore, Maryland, USA.
* Corresponding author. Academy for Educational Development, Food and Nutrition Technical Assistance (FANTA) Project, 1825 Connecticut Avenue NW, Washington DC, 20009. E-mail: mdeitchl{at}aed.org
 |
Abstract |
|---|
Background The conventional method for assessing the prevalence of Global Acute Malnutrition (GAM) in emergency settings is the 30 x 30 cluster-survey. This study describes alternative approaches: three Lot Quality Assurance Sampling (LQAS) designs to assess GAM. The LQAS designs were field-tested and their results compared with those from a 30 x 30 cluster-survey.
Methods Computer simulations confirmed that small clusters instead of a simple random sample could be used for LQAS assessments of GAM. Three LQAS designs were developed (33 x 6, 67 x 3, Sequential design) to assess GAM thresholds of 10, 15 and 20%. The designs were field-tested simultaneously with a 30 x 30 cluster-survey in Siraro, Ethiopia during June 2003. Using a nested study design, anthropometric, morbidity and vaccination data were collected on all children 6–59 months in sampled households. Hypothesis tests about GAM thresholds were conducted for each LQAS design. Point estimates were obtained for the 30 x 30 cluster-survey and the 33 x 6 and 67 x 3 LQAS designs.
Results Hypothesis tests showed GAM as <10% for the 33 x 6 design and GAM as 
10% for the 67 x 3 and Sequential designs. Point estimates for the 33 x 6 and 67 x 3 designs were similar to those of the 30 x 30 cluster-survey for GAM (6.7%, CI = 3.2–10.2%; 8.2%, CI = 4.3–12.1%, 7.4%, CI = 4.8–9.9%) and all other indicators. The CIs for the LQAS designs were only slightly wider than the CIs for the 30 x 30 cluster-survey; yet the LQAS designs required substantially less time to administer.
Conclusions The LQAS designs provide statistically appropriate alternatives to the more time-consuming 30 x 30 cluster-survey. However, additional field-testing is needed using independent samples rather than a nested study design.
Keywords Acute malnutrition, assessment, emergency, Ethiopia, lot quality assurance sampling, LQAS, wasting
Accepted 3 April 2007
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  P. Garner and G. D. Smith Information for decision making: lot quality assurance sampling in the spotlight Int. J. Epidemiol., February 1, 2010; 39(1): 5 - 6. [Full Text] [PDF]
|
|
|
|
|
|
S. Morris Commentary: Learning to Love Lot Quality Assurance Sampling Int. J. Epidemiol., August 1, 2007; 36(4): 864 - 865. [Full Text] [PDF]
|
|