UKURAN DAMPAK DALAM EPIDEMIOLOGI. Putri Handayani, M.KKK

Transkripsi

1 UKURAN DAMPAK DALAM EPIDEMIOLOGI Putri Handayani, M.KKK

2 Measures of Public Health Impact Attributable Risk (AR) Attributable Risk Percent (AR%) Number Percentage Population Attributable Risk (PAR) Number Population Attributable Risk Percent (PAR%) Percentage

3 Measures of Public Health Impact IMPORTANT! They all assume (require) that a cause-effect relationship exists between the exposure and the outcome.

4 Relative Risk vs. Attributable Risk Relative Risk: Measure of the strength of association, and indicator used to assess the possibility of a causal relationship. Attributable Risk: Measure of the potential for prevention of disease if the exposure could be eliminated (assuming a causal relationship).

5 Relative Risk vs. Attributable Risk Relative Risk: Etiology Attributable Risk: Policy decisions Funding decisions (e.g. prevention programs)

6 Tipe ukuran yang digunakan dalam epidemiologi Ukuran efek/dampak Merefleksikan dampak suatu faktor pada frekuensi atau risiko dari suatu masalah (outcome) kesehatan Merefleksikan kelebihan jumlah kasus karena suatu faktor (attributable) atau jumlah kasus yang dapat dicegah oleh eksposur (pemajan)

7 Ukuran-ukuran dampak Ukuran perbedaan dampak/efek Perbedaan risiko = Risk Difference (RD) = Attributable Risk (AR) = Excess Risk (ER) = Absolute Risk (AR) [Risiko pada kelompok terpajan] [Risiko pada kelompok tidak terpajan] Berguna untuk mengukur besarnya masalah kesehatan masyarakat yang disebabkan oleh suatu pemajan bermanfaat untuk penilaian prioritas untuk aksi kesehatan masyarakat (Public Health Action)

8 Among the EXPOSED: Attributable Risk (AR) How much of the disease that occurs can be attributed to a certain exposure? AR AR% This is of primary interest to the practicing clinician.

9 Attributable Risk (AR) AR = I exposed I nonexposed = Risk Difference Develop CHD I SM = 84 / 3000 Smoke Yes No = = 28.0 / 1000 Yes No I NS = 87 / 5000 = = 17.4 / 1000 (background risk) AR = ( ) / 1000 = 10.6 / 1000

10 Attributable Risk (AR) AR = ( ) / 1000 = 10.6 / 1000 Among SMOKERS, 10.6 of the 28/1000 incident cases of CHD are attributed to the fact that these people smoke Among SMOKERS, 10.6 of the 28/1000 incident cases of CHD that occur could be prevented if smoking were eliminated.

11 Ukuran-ukuran dampak Ukuran perbedaan dampak/efek Perbedaan insidens kumulatif = Cumulative Incidence Difference= CID [IK pada kelompok terpajan] - [IK pada kelompok tidak terpajan] IK = Insidens Kumulatif

12 Ukuran-ukuran dampak Ukuran perbedaan efek Perbedaan rate/ perbedaan densitas insidens (IDD = Insidence Density Difference) IDD = [Densitas insidens dalam kelompok terpajan] - [Densitas insidens pada kelompok tidak terpajan]

13 Ukuran-ukuran dampak Ukuran perbedaan efek Perbedaan prevalens (PD = Prevalence Differrence) PD = [Prevalens dalam kelompok terpajan] - [Prevalens dalam kelompok tidak terpajan]

14 Attributable Risk Incidence I exposed - I unexposed Exposed Unexposed

15 Ukuran-ukuran dampak/efek Ukuran perbedaan efek Attributable Risk (AR) Percent = AR% AR% Insidens terpajan Insidens Insidens terpajan tidak terpajan x100%

16 Attributable Risk Percent (AR%) AR% = (I exposed I nonexposed ) / I exposed = Etiologic fraction Develop CHD Smoke Yes No Yes No I SM = 84 / 3000 = = 28.0 / 1000 I NS = 87 / 5000 = = 17.4 / 1000 (background risk) AR% = ( ) / 28.0 = 37.9%

17 Attributable Risk Percent (AR%) AR% = ( ) / 28.0 = 37.9% Among SMOKERS, 38% of the morbidity from CHD may be attributed to smoking Among SMOKERS, 38% of the morbidity from CHD could be prevented if smoking were eliminated.

18 Attributable Risk Percent Incidence I exposed I unexposed RR = x 100% I exposed RR Exposed Unexposed

19 Ukuran-ukuran dampak Population Attributable Risk (PAR) = Attributable Fraction (population) atau Etiologic Fraction (population) = Population Attributable Risk Proportion = Population Attributable Risk Fraction Proporsi (atau fraksi) rate penyakit pada seluruh populasi yang mewakili rate penyakit dalam kelompok terpajan Rumus PAR PAR Insidens populasi Insidens tidak terpajan

20 Ukuran-ukuran dampak Population Attributable Risk Percent (PARP) attributable fraction (population) atau etiologic fraction (population) Berarti proporsi kasus baru yang dapat dicegah jika pada semua orang yang tidak terpajan Rumus PAR% PAR% Insidens populasi Insidens Insidens populasi tidak terpajan x100%

21 Population Attributable Risk Percent PAR% = (I total I nonexposed ) / I total Diabetes Weight Yes No Obese Slim I T = 1100 / = 0.11 = 110 / 1000 I NE = 250 / 5500 = = 45.5 / 1000 (background risk) PAR% = ( ) / 110 = 58.6%

22 Population Attributable Risk Percent PAR% = ( ) / 110 = 58.6% In Tampa, 59% of the cases of diabetes may be attributed to obesity in the population In Tampa, 59% of the cases of diabetes could be prevented if Tampa residents lost sufficient weight.

23 Prevented Fraction (PF) If relative risk <1 Proportion of potential new cases which would have occurred if the exposure had been absent Proportion of potential cases prevented by the exposure Iunexposed- Iexposed PF Iunexposed 1- RR

24 PF: Vaccine efficacy Pop. Cases Cases/1000 RR Vaccinated 301, Unvaccinated 298, Ref. Total 600, PF

25 Ringkasan ukuran Tipe Kuantitas Matematis Tanpa denominator Dengan denominator Enumerasi Hitung, angka mutlak Rasio Proporsi Rate

26 Ringkasan ukuran Tipe Kuantitas Matematis Enumerasi Rasio Proporsi Rate RR OR IDR % AR% PAR% Crude Spesific Adjusted

27 Ringkasan ukuran Ukuran dalam epidemiologi Ukuran Frekuensi Penyakit Ukuran asosiasi Ukuran efek /dampak

28 Ukuran frekuensi penyakit Ukuran frekuensi Penyakit Insidens Prevalens Mortalitas Insidens Kumulatif Incidence Density Prevalens titik Prevalens periode

29 Ukuran frekuensi penyakit Ukuran Rasio Risk Ratio Odds Rasio Insidence Density Ratio Prevalence Ratio

30 Ukuran frekuensi penyakit Ukuran Efek /dampak RD = Risk Difference AR = Attributable Risk ER = Excess Risk PAR = Population Attributable Risk PF = Prevented Fraction Perbedaan efek Fraksi Efek RD AR ER PAR AR% PAR% PF