PENGUKURAN RISIKO PENYAKIT Oleh Nugroho Pengantar Kejadian Penyakit

PENGUKURAN RISIKO PENYAKIT Oleh Nugroho

Pengantar • Kejadian Penyakit – Insiden – Prevalensi • Epidemiologi Deskriptif (Frekuensi Penyakit) – Rate – Ratio – Proporsi • Epidemiologi Analitik – Odd Rasio – Risiko Relatif

Kejadian Penyakit (Insiden) • Insiden merupakan kejadian kasus baru selama masa pengamatan.

Question 1. What is the ratio of males to females? 2. What proportion of infants lived? 3. What proportion of infants were delivered in a delivery room? 4. What is the ratio of operating room deliveries to delivery room deliveries?

Answer 1. a. 5 males, 6 females. male: female = 5: 6. Ratio of males to females is 5 to 6; 0. 83 to 1 2. b. 9 lived, 2 died. proportion lived = lived / all case = 9 / 11 =0. 82. Proportion of infants that lived is 82%or 8. 2 out of 10 3. c. 5 delivery room, 5 operating room, and 1 emergency room delivery. proportion delivery room deliveries = delivery room/ all cases =5/11 = 0. 45. Proportion of infants delivered in delivery room is 45% or 4. 5 out of 10 4. d. 5 delivery room and 5 operating room deliveries. delivery room: operating room = 5: 5 = 1: 1 Ratio of operating room deliveries to delivery room deliveries is 1 to 1.

Prevalensi

Insiden and prevalence

Question • Assume that we begin a study of 100 persons free of disease on January 1, and that on the last day of each month throughout the year, we will be given a count of new cases of disease in this population. Assume that over the course of a full year, 10 of these persons develop disease, and that 2 of these cases were reported on March 31, 3 more cases on June 30, 3 cases on September 30, and 2 cases on December 31. How many person-months did the study members contribute (assume patients became cases on the last day of the month).

Answer • (90 patients x 12 months) + (2 patient x 3 months) + (3 patients x 6 months) + (3 patients x 9 months) + (2 patients x 12 months) = 1155 person-months

Hubungan insiden dan prevalensi Insiden Prevalensi Mati/sembuh

Epidemiologi Analitik • Odd Rasio • Risiko Relative

Odds Ratio • Digunakan dalam penelitian case control • Menilai perbandingan atara kasus dan kontrol • Tidak mampu menilai laju risiko penyakit • Rumus

Relatif risk • Menilai laju kecepatan penyakit • Tepat digunakan pada desain penelitian kohort • Risiko relatif yang dinilai • Rumus

Latihan • Mahasiswa A 71. jika diketahui dalam perkuliahan biostatistik didapatkan 3 mahasiswa absen perempuan dan 6 mhs laki-laki. Jika diketahui mahasiswa perempuan 20 mahasiswa dan laki-laki 20 mahasiswa. • Pertanyaan… berapa resikonya mahasiswa perempuan di A 71 untuk tidak masuk biostatistik…?