Decentralization of Acid Fast Bacilli (AFB) External Quality Assurance Using Blind Rechecking for Sputum Smear Microscopy in Ethiopia.
PLoS One
; 11(3): e0151366, 2016.
Article
em En
| MEDLINE
| ID: mdl-26991651
ABSTRACT
INTRODUCTION:
Ethiopia achieved a rapid expansion of TB microscopic centers for acid fast bacilli (AFB). However, external quality assurance (EQA) services were, until recently, limited to few regional and sub-regional laboratories. In this paper, we describe the decentralization experience and the result of EQA using random blinded rechecking. MATERIALS ANDMETHODS:
The routine EQA quarterly report was compiled and analyzed. A positive result by the microscopic center while the EQA center reported negative result is categorized as false positive (FP). A negative result by the microscopic center while the EQA center reported positive is considered false negative (FN). The reading of EQA centers was considered a gold standard to compute the sensitivity, specificity, positive predictive (PPV) and negative predictive values (NPV) of the readings of microscopic centers.RESULTS:
We decentralized sputum smear AFB EQA from 4 Regional Laboratories (RRLs) to 82 EQA centers and enrolled 956 health facilities in EQA schemes. Enrollment of HFs in EQA was gradual because it required training and mentoring laboratory professionals, institutionalizing internal QA measures, equipping all HFs to perform diagnosis, and establishing more EQA centers. From 2012 to 2014 (Phase I), the FP rate declined from 0.6% to 0.2% and FN fell from as high as 7.6% to 1.6% in supported health facilities (HFs). In HFs that joined in Phase II, FN rates ranged from 5.6 to 7.3%. The proportion of HFs without errors has increased from 77.9% to 90.5% in Phase I HFs and from 82.9% to 86.9% in Phase II HFs. Overall sensitivity and specificity were 95.0% and 99.7%, respectively. PPV and NPV were 93.3% and 99.7%, respectively.CONCLUSION:
Decentralizing blinded rechecking of sputum smear microscopy is feasible in low-income settings. While a comprehensive laboratory improvement strategy enhanced the quality of microscopy, laboratory professionals' capacity in slide reading and smear quality requires continued support.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Controle de Qualidade
/
Escarro
/
Tuberculose Pulmonar
/
Técnicas Bacteriológicas
/
Laboratórios
/
Microscopia
/
Mycobacterium tuberculosis
Tipo de estudo:
Clinical_trials
/
Prognostic_studies
Limite:
Humans
País/Região como assunto:
Africa
Idioma:
En
Ano de publicação:
2016
Tipo de documento:
Article