EBM

Evidence Based Medicine

Kelompok 19

Erliana Tantri H(12/329139/KU/14928)Laksmi Damayanti (12/329146/KU/14933)Dyan Pramandita W.K (12/329196/KU/14968)Dinar Hanifah (12/329257/KU/15021)Fatimah Ayu Nuraeni(12/335477/KU/15172) ScenarioThe WHO recommends that in setting with a low prevalence and risk of malaria, diagnosis should be based on fever within past 3 days and possibility of exposure to malaria. In settings where malaria is endemic, diagnosis is based on fever within the past 24 hours, and signs of anemia. All diagnose should be confirmed with parasitological test. Recently, WHO also recommend rapid test to screen malaria. You wonder how good this rapid test to screen malaria in high endemic area.

PICOSearching Method

Reference: Stauffer, WM, Cartwright, CP, Olson, DA, Juni, BA, Taylor, CM, Bowers, SH, Hanson, KL, Rosenblatt, JE, Boulware, DR 2009,Diagnostic performance of rapid diagnostic tests versus blood smears for malaria in US clinical practice, Clin Infect Dis, Vol 49, No 6. pp.908-913

CRITICAL APPRAISALAre the result of the study valid?

This paper: YesComment: Sudah dijelaskan bahwa sampel yang digunakan adalah darah dari partisipan yang merupakan returning travelers yang berjumlah 852 orang.

This paper: YesComment: Pada artikel sudah tercantum dengan jelas, bahwa gold standard yang digunakan adalah Giemsa-stain blood smear dan digunakan RDT yaitu NOWMalaria Test sebagai pembanding.This paper: YesComment: Tertulis di artikel bahwa penelitian dilakukan dengan prinsip blind, tapi tidak dijelaskan apakah single-blinded atau double-blinded.

What were the result?

Intepretasi tabel :

Blood SmearTotal+-RDT +928100-3749952Total95757852RDT (all malaria)Sensitivity (Sn) = 92/95 = 97%Specificity (Sp) = 749/757 = 99%PPV = 92/100 = 92%NPV = 98%

Blood Smear (all malaria)Sensitivity (Sn) = 85%Specificity (Sc) = 100%PPV = 99%NPV = 93%Application(Methods: methods and measurement) Thick and thin Giemsa-stain blood smears were prepared from EDTA-anticoagulated venous blood. Smears were examined for the presence of malarial parasites by trained technologists or hematopathologists per individual laboratory protocol with a minimum of 500 high-powered fields examined. An expert pathologist or hematopathologist confirmed all positive smears. The NOWMalaria Test was performed per the manufacturers instructions by technologists masked to the blood smear results. The NOWMalaria Test is a lateral flow immunochromatographic test, similar to a pregnancy test with a visual result in < 15 minutes. A nested case-control study verified all positive and discrepant results by PCR in a separate laboratory, as previously described. [9] For each positive sample, two samples negative by both blood smear and rapid test served as masked, negative controls for PCR. Finally, unusual or discrepant PCR results were tested at separate laboratory by a second PCR method utilizing different primers [10] and using a second, independent DNA extraction to prevent contamination. For verifying discrepant results between RDT and blood smear, PCR served as the reference standard for validation. All personnel were masked to other test results, and no person performed more than one test type.

(Methods: outcome and data analysis) The primary outcome measure was the test performance of the RDT and traditional blood smear. Specifically, we were primarily interested in the sensitivity for malaria diagnosis and the NPV to exclude malaria of each diagnostic modality. Differences between the diagnostic performances were analyzed by using the two-tailed McNemars test to compare the paired, nominal data.

This paper: YesComment: Jurnal sudah menjelaskan prosedur pengujian sampel dan cara intepretasi serta validasi sampel, meskipun tidak terlalu dijelaskan dengan spesifik. Tetapi jika diterapkan di Indonesia belum tentu memberikan hasil yang sama karena perbedaan pola demografi dan geografi.Table of Evidence

Study samplesDalam penelitian ini, sampel yang digunakan adalah darah yang berasal dari returning traveler yang berasal dari 3 laboratorium rumah sakit sepanjang tahun 2003-2006.Bukti terdapat dalam :This prospective, operational laboratorystudy was conducted at the 3 hospital-based laboratories with the highest incidence of malaria in Minnesota from 1 March 2003 through 28 February 2006. All consecutive samples sent to the laboratories for thick and thin blood smears to test for malaria were included. Participants were returningtravelers, most of whom were visiting friends and relatives.Number of samples852Study settingsThis prospective, operational laboratory study was conducted at the 3 hospital-based laboratories with the highest incidence of malaria in Minnesota from 1 March 2003 through 28 February 2006.Study designprospective studyInterventionThick and thin Giemsa-stain blood smears were prepared from EDTA-anticoagulated venous blood. Smears were examined for the presence of malarial parasites by trained technologists or hematopathologists per individual laboratory protocol with a minimum of 500 highpowered fields examined.Polymerase chain reaction verified positive test results and discordant results.The rapid antigen capture assay is a lateral flow immunochromatographic test, similar to a pregnancy test, with a visual result in !15 min.ResultsMalaria was noted in 95 (11%) of the 852 samples. The RDT had superior performance than the standard Giemsa thick blood smear (Pp.003). The RDTs sensitivity for all malaria was 97% (92 of 95 samples), compared with 85% (81 of 95) for the blood smear, and the RDT had a superior NPV of 99.6%, compared with 98.2% for the blood smear (Pp.001). The P. falciparum performance was excellent, with 100% rapid test sensitivity,compared with only 88% (65 of 74) by blood smear (Pp.003).Conclusion This operational study demonstrates that the US Food and Drug Administrationapproved RDT for malaria is superior to a single set of blood smears performed under routine US clinical laboratory conditions.The most valuable clinical role of the RDT is in the rapid diagnosis or the exclusion of P. falciparum malaria, which is particularly useful in outpatient settings when evaluating febrile travelers.Results of critical appraisalKesimpulan terdapat di bawah.Discussion ReportQ: Apakah data pada jurnal ini dapat dipercaya?A: Ya, pertama dapat kita lihat dari hasil penelitian bahwa nilai p =0,01 dimana nilai p standar untuk dapat diterima secara statistic adalah p< 0,05 maka hasil penelitian ini dapat dipercaya dan signifikan secara statistic.

Q: Apakah menjawab pertanyaan ?A: Ya , dapat dilihat dari hasil penelitian yang menyatakan bahwa sensitivitas RDT untuk semua jenis malaria adalah 97%, lebih tinggi dibandingkan sensitivitas apusan darah tebal dan tipis yaitu 85%. Sedangkan spesifisitas dari RDT untuk semua jenis malaria adalah 99%, lebih rendah dibandingkan spesifisitas apusan darah tebal dan tipis yaitu 100%. Selain itu sensitivitas RDT untuk mendeteksi P.falciparum adalah 100%, lebih baik dibandingkan sensitivitas apusan darah tebal dan tipis yang hanya 88%.