crp k-5 critical appraisal

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CRITICAL CRITICAL APPRAISAL APPRAISAL (TELAAH KRITIS) (TELAAH KRITIS) PENELITIAN KEDOKTERAN PENELITIAN KEDOKTERAN

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Page 1: CRP K-5 Critical Appraisal

CRITICAL CRITICAL APPRAISALAPPRAISAL

(TELAAH KRITIS)(TELAAH KRITIS)PENELITIAN PENELITIAN

KEDOKTERANKEDOKTERAN

Page 2: CRP K-5 Critical Appraisal

TELAAH KRITIS = CRITICAL APPRAISALTELAAH KRITIS = CRITICAL APPRAISAL

Menambah pemahaman Mengikuti perkembangan

Melakukan penelitian

PENILAIAN HASIL PENELITIAN SECARA SISTEMATIS

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LANGKAH AWAL TELAAH KRITISLANGKAH AWAL TELAAH KRITIS

PENILAIAN JUDUL, PENILAIAN JUDUL, ABSTRAK DAN RUJUKANABSTRAK DAN RUJUKAN

PENILAIAN STRUKTUR DAN KELENGKAPAN

MAKALAH

CHECK LIST UMUM STRUKTUR DAN ISI

MAKALAH

PEMBAHASAN PEMBAHASAN TELAAH KRITISTELAAH KRITIS

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Penilaian struktur & Penilaian struktur & kelengkapan makalahkelengkapan makalah

Judul Nama pengarang & institusinya Abstrak Pendahuluan Metodologi penelitian Hasil Diskusi/pembahasan Ucapan terima kasih Daftar rujukan

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Sesuai dgn keperluan pembacaSesuai dgn keperluan pembaca Tidak terlalu panjang atau pendekTidak terlalu panjang atau pendek Masalah yang diteliti jelas / efisienMasalah yang diteliti jelas / efisien MenarikMenarik Tanpa singkatan, selain yang bakuTanpa singkatan, selain yang baku

PENILAIAN TERHADAP JUDULPENILAIAN TERHADAP JUDUL

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ABSTRAKABSTRAK

Informasi Informasi menyeluruh/ringkasmenyeluruh/ringkas

Latar belakang/tujuanLatar belakang/tujuan Rancangan penelitianRancangan penelitian

MetodologiMetodologi HasilHasil

KesimpulanKesimpulan SaranSaran

Kurang dari 250 kataKurang dari 250 kata

Page 7: CRP K-5 Critical Appraisal

RUJUKANRUJUKAN

Rujukan terbaru (Terutama jurnal hasil penelitian)

Penulisan yang tepat

Page 8: CRP K-5 Critical Appraisal

CHECK LIST UMUM STRUKTUR DAN CHECK LIST UMUM STRUKTUR DAN ISI MAKALAH ISI MAKALAH

CHECK LIST

YA

TIDAK

TIDAK RELEVAN

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PENDAHULUANPENDAHULUAN

1. Pendahuluan tdd 2 paragraf atau 2 bagian1. Pendahuluan tdd 2 paragraf atau 2 bagian

2. Paragraf atau bagian pertama mengemukakan 2. Paragraf atau bagian pertama mengemukakan alasan dilakukannya penelitianalasan dilakukannya penelitian

3. Paragraf atau bagian kedua menyatakan 3. Paragraf atau bagian kedua menyatakan hipotesis atau tujuan penelitianhipotesis atau tujuan penelitian

4. Paragraf kedua menyebutkan design yg 4. Paragraf kedua menyebutkan design yg digunakandigunakan

5. Pendahuluan didukung oeh pustaka yg kuat 5. Pendahuluan didukung oeh pustaka yg kuat dan relevandan relevan

6. Pendahuluan lebih dari 1 halaman6. Pendahuluan lebih dari 1 halaman

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METODEMETODE

1. Desain, tempat, dan waktu disebutkan1. Desain, tempat, dan waktu disebutkan

2. Populasi sumber disebutkan2. Populasi sumber disebutkan

3. Kriteria pemilihan inklusi dan eksklusi dijelaskan3. Kriteria pemilihan inklusi dan eksklusi dijelaskan

4. Tehnik Sampling disebutkan4. Tehnik Sampling disebutkan

5. Perkiraan besar sampel disebutkan dan 5. Perkiraan besar sampel disebutkan dan alasannyaalasannya

6. Perkiraan besar sampel dihitung dgn rumus yg 6. Perkiraan besar sampel dihitung dgn rumus yg sesuaisesuai

7. Komponen-komponen rumus besar sampel diisi 7. Komponen-komponen rumus besar sampel diisi dengan angka yang masuk akaldengan angka yang masuk akal

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METODEMETODE

8. Observasi, pengukuran serta intervensi dirinci 8. Observasi, pengukuran serta intervensi dirinci sehingga orang sehingga orang lain dapat mengulanginyalain dapat mengulanginya

9. Rujukan disebutkan bila teknik pengukuran tidak 9. Rujukan disebutkan bila teknik pengukuran tidak dirincidirinci

10. Pengukuran dilakukan secara tersamar10. Pengukuran dilakukan secara tersamar11. Uji keandalan pengukuran (kappa) dilakukan11. Uji keandalan pengukuran (kappa) dilakukan12. Definisi istilah dan variabel penting dikemukakan 12. Definisi istilah dan variabel penting dikemukakan 13. Ethical clearance diperoleh13. Ethical clearance diperoleh14. Persetujuan subjek diperoleh14. Persetujuan subjek diperoleh15. Disebutkan rencana analisis, batas kemaknaan, 15. Disebutkan rencana analisis, batas kemaknaan,

&&power penelitianpower penelitian16. Program komputer yang dipakai disebutkan16. Program komputer yang dipakai disebutkan

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HASILHASIL

1. Tabel deskripsi subyek penelitian disebutkan1. Tabel deskripsi subyek penelitian disebutkan2. Pada uji perbandingan, karakteristik subyek yang 2. Pada uji perbandingan, karakteristik subyek yang

penting penting sebelum intervensi dibandingkan sebelum intervensi dibandingkan kesetaraannyakesetaraannya

3. Uji hipotesis untuk kesetaraan dilakukan3. Uji hipotesis untuk kesetaraan dilakukan4. Jumlah subyek penelitian disebutkan4. Jumlah subyek penelitian disebutkan5. Subyek yang droup out dijelaskan beserta 5. Subyek yang droup out dijelaskan beserta

alasannyaalasannya6. Ketepatan numerik dinyatakan dengan benar6. Ketepatan numerik dinyatakan dengan benar7. Penulisan tabel dilakukan dengan tepat7. Penulisan tabel dilakukan dengan tepat8. Tabel dan iliustrasi bersifat informatif8. Tabel dan iliustrasi bersifat informatif9. Tabel dan ilustrasi memang diperlukan9. Tabel dan ilustrasi memang diperlukan

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HASILHASIL

10. Semua hasil dalam tabel disebutkan didalam 10. Semua hasil dalam tabel disebutkan didalam nas.nas.

11. Semua outcome yang penting disebutkan 11. Semua outcome yang penting disebutkan dalam hasildalam hasil

12. Subyek yang drop out diikutkan dalam analisis12. Subyek yang drop out diikutkan dalam analisis13. Analisis dilakukan dengan uji yang sesuai13. Analisis dilakukan dengan uji yang sesuai14. Hasil uji statistik disertakan, derajat kebebasan 14. Hasil uji statistik disertakan, derajat kebebasan

dan nilai dan nilai pp disertakan disertakan15. Tidak dilakukan analisis yang semula tidak 15. Tidak dilakukan analisis yang semula tidak

direncanakandirencanakan16. Interval kepercayaan disertakan16. Interval kepercayaan disertakan17. Komentar dan pendapat tidak disertakan dalam 17. Komentar dan pendapat tidak disertakan dalam

hasilhasil

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DISKUSIDISKUSI

1. Semua hasil yang relevan dibahas1. Semua hasil yang relevan dibahas2. Hal yang dikemukakan dalam hasil sering diulang2. Hal yang dikemukakan dalam hasil sering diulang3. Dibahas keterbatasan hasil penelitian, dan 3. Dibahas keterbatasan hasil penelitian, dan

kemungkinan dampaknya terhadap hasilkemungkinan dampaknya terhadap hasil4.Diskusi menyebutkan kesulitan penelitan, 4.Diskusi menyebutkan kesulitan penelitan,

penyimpangan dari protokol, dan kemungkinan penyimpangan dari protokol, dan kemungkinan dampaknya terhadap hasildampaknya terhadap hasil

5.Pembahasan dihubungkan dengan pertanyaan 5.Pembahasan dihubungkan dengan pertanyaan penelitianpenelitian

6.Pembahasan dihubungkan dengan teori dan hasil 6.Pembahasan dihubungkan dengan teori dan hasil peneltian terdahulupeneltian terdahulu

7. Dibahas hubungan hasil dengan praktek klinis7. Dibahas hubungan hasil dengan praktek klinis8. Disertakan kesimpulan utama penelitian8. Disertakan kesimpulan utama penelitian. .

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DISKUSIDISKUSI

9. Kesimpulan didasarkan pada data penelitian9. Kesimpulan didasarkan pada data penelitian

10. Kesimpulan bersifat shahih10. Kesimpulan bersifat shahih

11. Diskusi mengemukakan dan membahas efek 11. Diskusi mengemukakan dan membahas efek samping samping

12. Hasil tambahan selama observasi, disebutkan12. Hasil tambahan selama observasi, disebutkan

13. Hasil tambahan dianalisis secara statistik13. Hasil tambahan dianalisis secara statistik

14. Generalisasi hasil penelitan, disebutkan14. Generalisasi hasil penelitan, disebutkan

15. Diskusi disertakan saran penelitian 15. Diskusi disertakan saran penelitian selanjutnya, dengan anjuran metodologis yang selanjutnya, dengan anjuran metodologis yang tepattepat

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UCAPAN TERIMA KASIHUCAPAN TERIMA KASIH

1. Ucapan terima kasih ditujukan kpd 1. Ucapan terima kasih ditujukan kpd orang-orang yang tepatorang-orang yang tepat

2. Ucapan terima kasih dinyatakan 2. Ucapan terima kasih dinyatakan secara wajarsecara wajar

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Critical AppraisalCritical Appraisal

On Article of Diagnostic Test On Article of Diagnostic Test

(EBM-Diagnostic)(EBM-Diagnostic)

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Critical appraisal is one step in the process of evidence-based clinical practice.

To determine what is the best evidence, we need critical appraisal skills that will help us to understand the methods and results of research and to assess the quality of the research.

Most research is not perfect, and critical appraisal is not an exact science - it will not give us the “right” answer. But it can help us to decide whether we think a reported piece of research is good enough to be used in decision making.

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Critical Appraisal - Worksheet for Critical Appraisal - Worksheet for critical appraisalcritical appraisal

- Software : CAT - Software : CAT MakerMaker

Main area of clinical objectives:Main area of clinical objectives: 1. Diagnosis1. Diagnosis 2. Prognosis2. Prognosis 3. Therapy/Treatment3. Therapy/Treatment 4. Risk/Harm4. Risk/Harm

Others:Others: Systematic Review and Meta-analysis Systematic Review and Meta-analysis Clinical GuidelinesClinical Guidelines Clinical Decision Making etc.Clinical Decision Making etc.

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THREE MAIN ASPECTS TO BE APPRAISED: THREE MAIN ASPECTS TO BE APPRAISED: V I AV I A

1. 1. VALIDITY :VALIDITY :

VALID (CLOSENESS TO THE TRUTH) VALID (CLOSENESS TO THE TRUTH) IN THE IN THE METHODOLOGY SECTIONMETHODOLOGY SECTION

2. 2. IMPORTANCE :IMPORTANCE :

IMPORTANT (USEFULNESS) IMPORTANT (USEFULNESS) IN THE RESULTS IN THE RESULTS SECTIONSECTION

3. 3. APPLICABILITY :APPLICABILITY :

APPLICABLE (CAN BE APPLIED IN CLINICAL APPLICABLE (CAN BE APPLIED IN CLINICAL PRACTICE) PRACTICE) IN THE DISCUSSION SECTION IN THE DISCUSSION SECTION

Page 21: CRP K-5 Critical Appraisal

DIAGNOSIS WORKSHEET

Citation:

Are the results of this diagnostic study valid?

Was there an independent, blind comparison with a reference (“gold”) standard of diagnosis?

Was the diagnostic test evaluated in an appropriate spectrum of patients (like those in whom it would be used in practice)?

Was the reference standard applied regardless of the diagnostic test result?

Was the test (or cluster of tests) validated in a second, independent group of patients?

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Are the valid results of this diagnostic study important?SAMPLE CALCULATIONS

Target disorder(iron deficiency anemia)

Totals

Present Absent

Diagnostic test result

(serum ferritin)

Positive(< 65 mmol/L)

731a

270b

1001a+b

Negative ( 65 mmol/L)

78c

1500d

1578c+d

Totals 809a+c

1770b+d

2579a+b+c+d

Sensitivity = a/(a+c) = 731/809 = 90%Specificity = d/(b+d) = 1500/1770 = 85%Likelihood ratio for a positive test result = LR+ = sens/(1-spec) = 90%/15% = 6Likelihood ratio for a negative test result = LR - = (1-sens)/spec = 10%/85% = 0.12Positive Predictive Value = a/(a+b) = 731/1001 = 73%Negative Predictive Value = d/(c+d) = 1500/1578 = 95%Pre-test probability (prevalence) = (a+c)/(a+b+c+d) = 809/2579 = 32%Pre-test odds = prevalence/(1-prevalence) = 31%/69% = 0.45Post-test odds = pre-test odds LRPost-test probability = post-test odds/(post-test odds +1)

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YOUR CALCULATIONS

Target disorderTotals

Present Absent

Diagnostic test result

Positive a b a+b

Negative c d c+d

Totals a+c b+d a+b+c+d

Page 25: CRP K-5 Critical Appraisal

• SnNoutSnNout• SnNoutSnNout

Diagnostic test with a very high sensitivity , a negative result effectively rules out the diagnosis

• SpPinSpPin

Diagnostic test with a very high specificity , a positive result effectively rules in the diagnosis

Page 26: CRP K-5 Critical Appraisal

Can you apply this valid, important evidence about a diagnostic test in caring for your patient?

Is the diagnostic test available, affordable, accurate, and precise in your setting?

Can you generate a clinically sensible estimate of your patient’s pre-test probability (from personal experience, prevalence statistics, practice databases, or primary studies)?Are the study patients similar to your own?Is it unlikely that the disease possibilities or probabilities have changed since the evidence was gathered?

Will the resulting post-test probabilities affect your management and help your patient?Could it move you across a test-treatment threshold?Would your patient be a willing partner in carrying it out?

Would the consequences of the test help your patient?

Additional notes:

Page 27: CRP K-5 Critical Appraisal
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Apakah ada perbandingan, independen buta dengan referensi Apakah ada perbandingan, independen buta dengan referensi ("emas") standar diagnosis?("emas") standar diagnosis?

Apakah tes diagnostik dievaluasi dalam spektrum yang sesuai Apakah tes diagnostik dievaluasi dalam spektrum yang sesuai pasien (seperti di yang akan digunakan dalam praktek)?pasien (seperti di yang akan digunakan dalam praktek)?

Apakah standar referensi diterapkan tanpa hasil uji diagnostik?Apakah standar referensi diterapkan tanpa hasil uji diagnostik? Apakah tes (atau kelompok tes) divalidasi dalam kelompok, Apakah tes (atau kelompok tes) divalidasi dalam kelompok,

kedua pasien independen?kedua pasien independen?

Apakah tes diagnostik yang tersedia, terjangkau, akurat, dan Apakah tes diagnostik yang tersedia, terjangkau, akurat, dan tepat dalam pengaturan Anda?tepat dalam pengaturan Anda?

Dapatkah Anda menghasilkan perkiraan klinis yang masuk akal Dapatkah Anda menghasilkan perkiraan klinis yang masuk akal dari probabilitas pre-test pasien Anda (dari pengalaman pribadi, dari probabilitas pre-test pasien Anda (dari pengalaman pribadi, statistik prevalensi, database praktek, atau studi utama)?statistik prevalensi, database praktek, atau studi utama)?

• Apakah pasien penelitian serupa dengan Anda sendiri?• Apakah pasien penelitian serupa dengan Anda sendiri?• Apakah tidak mungkin bahwa kemungkinan penyakit • Apakah tidak mungkin bahwa kemungkinan penyakit

atau atau probabilitas telah berubah sejak bukti itu dikumpulkan?probabilitas telah berubah sejak bukti itu dikumpulkan?Apakah post-test sehingga mempengaruhi probabilitas Apakah post-test sehingga mempengaruhi probabilitas

manajemen Anda dan membantu pasien Anda?manajemen Anda dan membantu pasien Anda?• Mungkinkah menggerakkan Anda melintasi ambang tes-• Mungkinkah menggerakkan Anda melintasi ambang tes-perawatan?perawatan?• Apakah pasien Anda bersedia menjadi mitra dalam • Apakah pasien Anda bersedia menjadi mitra dalam

menjalankan test?menjalankan test? Apakah konsekuensi dari uji membantu pasien Anda? Apakah konsekuensi dari uji membantu pasien Anda?

Page 31: CRP K-5 Critical Appraisal

Bedside Diagnosis Bedside Diagnosis of Influenzavirus of Influenzavirus

Infections in Infections in Hospitalized Hospitalized

ChildrenChildren

Katherine A. Poehling, et alKatherine A. Poehling, et alAmerican Academy of PediatricsAmerican Academy of Pediatrics

Example : an article of diagnostic test, entitle : Example : an article of diagnostic test, entitle :

Page 32: CRP K-5 Critical Appraisal

Background:Background: Influenzavirus has a significant impact on the

pediatric population, with school-aged children having the highest infection rates.

For preventing nosocomial influenza infections and to facilitate prompt antiviral therapy, an accessible, rapid diagnostic method for influenzavirus is needed.

Objective:Objective: To compare the performance of a rapid

diagnostic test (QuickVue Influenza Test; Quidel Corp, San Diego, CA) completed at the bedside of hospitalized children to viral culture and/or polymerase chain reaction (PCR) for influenzavirus.

Page 33: CRP K-5 Critical Appraisal

Method:Method: Study population:

1) younger than 19 years and hospitalized with respiratory symptoms or 2) younger than 3 years and hospitalized with fever.

Sampel: 1) a primary admission diagnosis of an acute respiratory illness characterized by rhinorrhea, sore throat, cough, shortness of breath, or apnea or 2) a primary admission diagnosis consistent with a febrile illness and a temperature of 100.4°F.

Broad inclusion criteria were chosen such that all children who were hospitalized with symptoms potentially related to influenza infections were eligible.

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Sample in this study

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Study design: Study design: prospective, cross sectional study prospective, cross sectional study f from each child, 2 nasal swabs of the turbinates were obtained—1 for influenzavirus culture and PCR and the other for the rapid diagnostic test. The rapid test results were compared with that of culture and PCR for influenzavirus.

Influenza infection was defined as any sample with 1) a positive culture for influenzavirus or 2) 2 consecutive positive PCRs for influenza A or B.

Each researcher was trained to perform and interpret the rapid diagnostic test at the bedside according to the manufacturer’s instructions.

The laboratory technician who performed the culture and PCR was masked to the rapid diagnostic test results.

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Results:Results:

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Sens: 74%Spec: 98%PPV: 74%NPV: 98%

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DIAGNOSIS WORKSHEET

Citation:

Are the results of this diagnostic study valid?

Was there an independent, blind comparison with a reference (“gold”) standard of diagnosis?

YesYes

Was the diagnostic test evaluated in an appropriate spectrum of patients (like those in whom it would be used in practice)?

YesYes

Was the reference standard applied regardless of the diagnostic test result?

YesYes

Was the test (or cluster of tests) validated in a second, independent group of patients?

YesYes

Page 39: CRP K-5 Critical Appraisal

Are the valid results of this diagnostic study important?

SAMPLE CALCULATIONS

Target disorderTotals

Present Absent

Diagnostic test result

Positive a b a+b

Negative c d c+d

Totals a+c b+d a+b+c+d

Page 40: CRP K-5 Critical Appraisal

++ --

++ 1414 55

-- 55 202099

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Culture or PCR Totals

Present Absent

Quick Vue Influenza

test

Positive 14 5 19

Negative 5 209 214

Totals 19 214 233Sensitivity = a/(a+c) = 14/19 = 74%Specificity = d/(b+d) = 209/214 =98%

Likelihood ratio for a positive test result = LR+ = sens/(1-spec) = 74%/2% = 37Likelihood ratio for a negative test result = LR - = (1-sens)/spec = 26%/98% = 0.27

Positive Predictive Value = a/(a+b) = 14/19 = 74%Negative Predictive Value = d/(c+d) = 209/214 = 98%

Pre-test probability (prevalence) = (a+c)/(a+b+c+d) = 19/233 = 8%

Pre-test odds = prevalence/(1-prevalence) = 8%/92% = 0.087Post-test odds = pre-test odds LR = 0.087 x 37 = 3.22Post-test probability = post-test odds/(post-test odds +1)= 3.22/4.22=76%

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Just to remind you:Just to remind you:

Sensitivity: the percentage of persons Sensitivity: the percentage of persons with the disease of interest who have with the disease of interest who have positive test results.positive test results.

= a/(a+c) x 100= a/(a+c) x 100

Specificity: the percentage of persons Specificity: the percentage of persons without the disease of interest who without the disease of interest who have negative results.have negative results.

= d/(d+b) x 100= d/(d+b) x 100

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PPV: the percentage of persons with PPV: the percentage of persons with positive test results who actually positive test results who actually have the disease of interest.have the disease of interest.= a/(a+b) x 100= a/(a+b) x 100

NPV: the percentage of persons with NPV: the percentage of persons with negative test results who do not negative test results who do not have the disease of interest.have the disease of interest.= d/(d+c) x 100= d/(d+c) x 100

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Likelihood RatioLikelihood Ratio

Likelihood is the probability of a Likelihood is the probability of a particular test result for a person with the particular test result for a person with the disease of interest divided by the disease of interest divided by the probability of that test result for a person probability of that test result for a person without the disease of interest. without the disease of interest.

Likelihood Ratio for a positive test result Likelihood Ratio for a positive test result (LR(LR++))

Likelihood Ratio for a negative test result Likelihood Ratio for a negative test result (LR(LR--))

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(LR(LR++) is the probability of a positive test ) is the probability of a positive test result for a person with the disease of result for a person with the disease of interest divided by the probability of a interest divided by the probability of a positive test result for a person without the positive test result for a person without the disease.disease.

LRLR++ = Sensitivity / (1-Specificity) = Sensitivity / (1-Specificity) LRLR+ + > 1: persons affected with disease of > 1: persons affected with disease of

interest are more likely to have a positive interest are more likely to have a positive test result than unaffected persons.test result than unaffected persons.

The larger the value of the LR, the stronger The larger the value of the LR, the stronger the association between having a positive the association between having a positive test result and having the disease of test result and having the disease of interest.interest.

LRLR++ value of 10 or greater is perceived as value of 10 or greater is perceived as indication of a test of high diagnostic value.indication of a test of high diagnostic value.

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LRs >10 or <0.1 cause large LRs >10 or <0.1 cause large changes in likelihood.changes in likelihood.

LRs 5-10 or 0.1-0.2 cause LRs 5-10 or 0.1-0.2 cause moderate changes.moderate changes.

LRs 2-5 or 0.2-0.5 cause small LRs 2-5 or 0.2-0.5 cause small changes.changes.

LRs between <2 and 0.5 cause LRs between <2 and 0.5 cause little or no changelittle or no change

LRs >10 or <0.1 cause large LRs >10 or <0.1 cause large changes in likelihood.changes in likelihood.

LRs 5-10 or 0.1-0.2 cause LRs 5-10 or 0.1-0.2 cause moderate changes.moderate changes.

LRs 2-5 or 0.2-0.5 cause small LRs 2-5 or 0.2-0.5 cause small changes.changes.

LRs between <2 and 0.5 cause LRs between <2 and 0.5 cause little or no changelittle or no change

LIKELIHOOD RATIOLIKELIHOOD RATIO

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Pretest probability of diseasePretest probability of disease: the probability : the probability that a person has the disease of interest before that a person has the disease of interest before the test is performed. the test is performed.

= prevalence= prevalence

Pretest odds of diseasePretest odds of disease: the estimate before : the estimate before diagnostic testing of the probability that a diagnostic testing of the probability that a patient has the disease of interest divided by patient has the disease of interest divided by the probability that the patient does not have the probability that the patient does not have the disease of interest.the disease of interest.

Pretest odds= pretest probability/(1-pretest Pretest odds= pretest probability/(1-pretest probability)probability)

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Posttest odds of disease: as the estimate after diagnostic testing of the probability that a patient has the disease of interest divided by the probability that the patient does not have the disease of interest.

Posttest odds= pretest odds x LR +

Posttest probability = posttest odds/ (1+posttest odds)

a result of obtaining a positive test result, the estimated probability of the presence of disease has risen from 0.08 (pretest probability) to 0.76 (posttest probability).

Diagnostic tests that produce big changes from pretest to post-test probabilities are important and likely to be useful to us in our practice

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Software: CAT Maker……Software: CAT Maker……

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Can you apply this valid, important evidence about a diagnostic test in caring for your patient?

Is the diagnostic test available, affordable, accurate, and precise in your setting? NoNoCan you generate a clinically sensible estimate of your patient’s pre-test probability (from personal experience, prevalence statistics, practice databases, or primary studies)?Are the study patients similar to your own?Is it unlikely that the disease possibilities or probabilities have changed since the evidence was gathered?

Yes Yes

YesYes

Will the resulting post-test probabilities affect your management and help your patient?Could it move you across a test-treatment threshold?Would your patient be a willing partner in carrying it out?

YesYes

Would the consequences of the test help your patient?YesYes

Additional notes:

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Thank Thank you…..you…..