Diffusion of subsidized ACTs in accredited drug shops in Tanzania: determinants of stocking and characteristics of early and late adopters

BMC Health Services Research

Jessica L Cohen³  Oliver Sabot²  Julius Massaga⁴  Jean Arkedis⁶  Sarah Alphs¹  Prashant Yadav⁵  Peter S Larson¹ 

[1] The William Davidson Institute, University of Michigan, 724 E University Avenue, Ann Arbor, MI 48109, USA;Clinton Health Access Initiative, 383 Dorchester Avenue, Suite 400, Boston, MA 02127, USA;Harvard School of Public Health, 677 Huntington Avenue, Boston, MA 02115, USA;National Institute for Medical Research, P.O. Box 9653, Dar es Salaam, Tanzania;School of Public Health, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109, USA;Results for Development Institute, 1100 15th Street, NW, Suite 400, Washington, DC, USA

关键词: Product diffusion;    Marketing;    Tanzania;    Drug shops;    ACT;    Malaria;   

Others  :  1134437
DOI  :  10.1186/1472-6963-13-526

 received in 2013-03-14, accepted in 2013-12-11,  发布年份 2013

【 摘 要 】

Background

Many households in sub-Saharan Africa utilize the private sector as a primary source of treatment for malaria episodes. Expanding access to effective treatment in private drug shops may help reduce incidence of severe disease and mortality. This research leveraged a longitudinal survey of stocking of subsidized artemisinin combination therapies (ACTs), an effective anti-malarial, in Accredited Drug Dispensing Outlets (ADDOs) in two regions of Tanzania. This provided a unique opportunity to explore shop and market level determinants of product diffusion in a developing country retail market.

Methods

356 ADDOs in the Rukwa and Mtwara regions of Tanzania were surveyed at seven points between Feb 2011 and May 2012. Shop level audits were used to measure the availability of subsidized ACTs at each shop. Data on market and shop level factors were collected during the survey and also extracted from GIS layers. Regression and network based methodologies were used. Shops classified as early and late adopters, following Rogers’ model of product diffusion, were compared. The Bass model of product diffusion was applied to determine whether shops stocked ACTs out of a need to imitate market competitors or a desire to satisfy customer needs.

Results

Following the introduction of a subsidy for ACTs, stocking increased from 12% to nearly 80% over the seven survey rounds. Stocking was influenced by higher numbers of proximal shops and clinics, larger customer traffic and the presence of a licensed pharmacist. Early adopters were characterized by a larger percentage of customers seeking care for malaria, a larger catchment and sourcing from specific wholesalers/suppliers. The Bass model of product diffusion indicated that shops were adopting products in response to competitor behavior, rather than customer demand.

Conclusions

Decisions to stock new pharmaceutical products in Tanzanian ADDOs are influenced by a combination of factors related to both market competition and customer demand, but are particularly influenced by the behavior of competing shops. Efforts to expand access to new pharmaceutical products in developing country markets could benefit from initial targeting of high profile shops in competitive markets and wholesale suppliers to encourage faster product diffusion across all drug retailers.

【 授权许可】

   
2013 Larson et al.; licensee BioMed Central Ltd.

【 图 表 】

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