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1
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• ????, ??????? ????????????? ????????,
• ????????? ????????? ??????????????? ???????????
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• ???????? ??????????? ????????

2
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• Prof. Charles Normand (LSHTM, ASPHER) ??
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• Prof. Y. Friedlander (HU-BHSPHCM) ?? ?????? ?
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• ?????????? ????????? ?????? ????????????? ?
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• ????? ? ???????? ?? ???? ? ??? ???????? ????

3
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• ??? ????? ???????? ? ?????????? ?????????????
• ??????? ? ??????????? ????????????
• ??? ????????, ?????????? ??? ??????????
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• ?????? ????????????? ?????????? ??? ????????????
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• ??????? ???????

4
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5
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??????????, ?????????? ?? ???????
????? ?????????????? ?? ??? ???????????
???????????? (?
????????? ??????????, ?????????? ?????
??????????? ?- ? ß-??????)
6
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• ?????? ??????
• ?????? ?????
• ?????? ???????
• ?????? ???????? ???? (?)

7
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• ? ????????? ?????????????
• ? ????????? ??????? ???????????? ???????? ?
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8
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• ??? ??????? ???????????????? ????????
• ???
• ??? ???????? ?????? ?????? selection bias
• ?
• ????????? ? ????? ????????? ?????? ?? ????, ???
  ??????????? ????? ?? ??????????? ???????????? ?
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9
??????? ???????????? ???????. ??????? ?
????????????

• ??????? ?? ?????????? ?? ????????????
  non-probability samples
• ??????? ????????????? probability samples
• ???????????? randomization

10
???? ??????? ?? ?????????? ?? ????????????

• ????????????? ??????? grab sample
• ??????? ??????? sample of convenience
• ??????????????? ??????? systematic sample

11
???? ????????????? ???????

• ??????? ????????? simple random sample
• ?????????? ??????? cluster sample
• ?????????????????? ??????? stratified sample
• ?????? ??????? zone sample
• ???????????? ??????? multilevel sample

12
??????? ????????? ???????
?????? (?/? ?????) ?????? ????????? ?????????
????? ????????? PEPI
13
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?????? ????? ???? ?????? ???? ???????????
14
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??????? ????????????? ??????????? ???????????? ??
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15
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16
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• ?????? ???? ??????
• ?????? ???? ??????????
• ?????? ???? ?????????????????? ?? ????

17
??????? ?? ?- ? ß-??????
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??????? ???????? ???????
???
??
ß-??????
??
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?-??????
???
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18
?- ? ß-?????? ? ?????????? ????????????

• ??????????? ?????? P value, ???????? p.
• ????? ???????? p ?? ????? ??????????
• p? lt0.05
• pß lt0.2 (0.1)
• ??? ????? p? lt0.05 pß lt0.2
• 0.05 0.2
• 5 20
• 1/20 1/5

19
???????? p? ??? ???????
???????? p lt0.05 ??????? ? ???, ??? ? ????? ?????
???????? ?? ??????-?????? ????????? ????? ??? ?
5 ??????? ?????????? ???????????, ???????? ??
???? ?? ?????? ????????? ??????? ?? ???????????
????????????, ??? ??? ?????? ??? ???? ??????? ??
???????? ?? ????? ????????? ???????????? ?? ?????
????????? ??????????? ????????????
???
????? ???
95 (????? ??? 19 ?? 20) ???? ????? ??????? ?????
????????? ???????????? ??????????? ????????????.
20
?????? ???????
?? ???? ??????? ??????????? ?????????? ??????
????????
21
??????????????????, ??????? ????? ??????? ?
???????? ??????????
????? ????????????? ????? ????? ???????????????
???????? ?? ?????? ?????? ???????????
?????? ??????? ??????? ?? ??????? ???????????
????????????, ?.?. ?? ??????????????????
????????? ??? ????? ??? ????? ???????, ????????
?????????? ?????????????? ??????????
22
?????? ????????? ????????, ???????
????????
????? ????????????? ????? ????? ???????????????
???????? ?? ?????? ?????? ???????????
?????? ??????? ??????? ?? ??????? ?????????,
???????? ???????? ???????? ??? ?? ?????????
????????? ??????????
23
???????? ????????????? ????????
????? ????????????? ????? ????? ???????????????
???????? ?? ?????? ?????? ???????????
??? lt100, 100-109, 110-119 ???lt100, 100-139,
140-169
?????? ??????? ??????? ?? ???????? ????????,
??????? ?? ????? ?????
24
???????? ? ? ß ??????
????? ????????????? ????? ????? ???????????????
???????? ?? ?????? ?????? ???????????
a(ß) 0.05 a(ß) 0.35
?????? ??????? ??????? ?? ??????? ?????????? a ?
ß ??????
25
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??? ??????????? ?????????????
?? ??????????? ?????? ??????? ?????
??????????????????, ??????? ????? ??????? ???
???????? ????????? ?????????? a ? ß- ??????
?????? 0.05 ? 0.2(0.1) ?????????????? ???
??????????? ???????? ????????, ???????????
???????? ???? ?????????????
Z? (??? ?0.05) 1.96 Zß (??? ß0.2) 0.84
26
??? ??????? t - ?????

• n ?????????? ???
• Sd ??????????? ?????????? ??? n ????????
• D ??????????? ???????? ????????
• Za ??? a5 1.96
• Zß ??? ß20 0.84

27
??? ???? ??????????? ?????

• n ?????? ?????? (??? ???????, ??? nn1n2
• S ??????????? ?????????? ??? n ????????
• D ??????????? ???????? ????????
• Za ??? a5 1.96
• Zß ??? ß20 0.84

28
??? ????????? ?????????

• ????????? ??????? ????? ???????
• ?????? ? ???????????? ? ?????????????? ?????
  ?????????? ?????????? ???????
• ??? ???? ???? ??????? ???????? n, ??? ?????? ????
  ? ???????????????? ? ???? ??????? ???????????
  ß-??????

29
??? ????????? ????????? (2)

• n ?????? ????? 1 ? 2, ??? ???????, ??? nn1n2
• p (????1????2)/(??????1??????2)
• D ?????????? ?????????? ????????
• Za 1.96
• Zß 0.84

30
??? ?????? ????????

• n ?????? ??????
• Za 1.96
• SD ??????????? ?????????? ??? ??????????
  ????????
• M ???????? ?????????? ??????????

31
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• ?????? ????? ??????????? ?????? ??? ???????
  ???????????? ??????? ???????
• ???????????? ??????
• ???????? ????????????
• ??????????? ??????????? ???????????? ?????????
  (PEPI)
• ???????? ?????????? ??????