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10.8 °“√§”π«≥¢π“¥µ—«Õ¬à“ß„π°“√‡ª√’¬∫‡∑’¬∫°“√√Õ¥™’æ

„πß“π«‘®—¬‡™‘ß«‘‡§√“–Àå·≈–ß“π«‘®—¬‡™‘ß∑¥≈Õß∑’Ë¡’µ—«·ª√º≈‡ªìπ√–¬–‡«≈“¢Õß°“√ª≈Õ¥

‡Àµÿ°“√≥åÀ√◊Õ°“√√Õ¥™’æ (survival) ®–‡ª√’¬∫‡∑’¬∫§à“¡—∏¬∞“π°“√ª≈Õ¥‡Àµÿ°“√≥å¥â«¬ log rank
test °“√§”π«≥¢π“¥µ—«Õ¬à“߇æ◊ËÕ°“√‡ª√’¬∫‡∑’¬∫§à“¡—∏¬∞“π√–¬–‡«≈“°“√√Õ¥™’æ (median
survival) √–À«à“ß°≈ÿà¡∑¥≈Õß°—∫°≈ÿࡧ«∫§ÿ¡ ®–‡√‘Ë¡µâπ‚¥¬°“√§”π«≥®”π«π°“√‡ ’¬™’«‘µ∑’ˇ撬ßæÕ

∑’Ë®–√–∫ÿ§«“¡µà“ß®“° Ÿµ√

4(Z a/ 2 + Z b ) 2
d=
q 2
R
‚¥¬∑’Ë ˜ = log y
R R
log S T [ ( )t ]
y =
R c [ ]
log S ( )t

‡¡◊ËÕ d = ®”π«π°“√‡ ’¬™’«‘µ
˜ = log (Õ—µ√“ à«π°“√‡ ’ˬ߿¬—πµ√“¬)
R
y =Õ—µ√“ à«π°“√‡ ’ˬ߿¬—πµ√“¬
R
S (t) = Õ—µ√“°“√√Õ¥™’æ¢Õß°≈ÿà¡∑¥≈Õß
T
S (t) = Õ—µ√“°“√√Õ¥™’æ¢Õß°≈ÿࡧ«∫§ÿ¡
c
„π°“√§”π«≥§à“ ‚ª√·°√¡§”π«≥¢π“¥µ—«Õ¬à“ß®–„Àâπ—°«‘®—¬°”Àπ¥§à“¡—∏¬∞“π√–¬–‡«≈“
°“√√Õ¥™’æ¢Õß°≈ÿà¡∑¥≈Õß·≈–°≈ÿࡧ«∫§ÿ¡ ´÷ËßµâÕßπ”¡“®“°°“√»÷°…“∑’˺à“π¡“ °√≥’∑’ËÀ“§à“¡—∏¬∞“π
√–¬–‡«≈“°“√√Õ¥™’æ¢Õß°≈ÿà¡∑¥≈Õ߉¡à‰¥â „Àâπ—°«‘®—¬ª√–¡“≥§à“ª√– ‘∑∏‘º≈¢Õß°“√√—°…“„π°≈ÿà¡

∑¥≈Õß«à“®–∑”„Àâ§à“¡—∏¬∞“π√–¬–‡«≈“°“√√Õ¥™’æ‡æ‘Ë¡¢÷Èπ®“°°≈ÿࡧ«∫§ÿ¡‡∑à“„¥
π”§à“ d ·≈–§«“¡πà“®–‡ªìπ¢Õß°“√‡ ’¬™’«‘µ„π™à«ß√–¬–‡«≈“°“√µ‘¥µ“¡ºŸâªÉ«¬ (Pr. (death))

¡“§”π«≥¢π“¥µ—«Õ¬à“ߢÕß®”π«πºŸâªÉ«¬∑’Ëπ”‡¢â“»÷°…“®“° Ÿµ√
d
n=
Pr. (death)
1
‚¥¬∑’Ë Pr. (death) = 1 - @S(F) + 4S(0.5A + F) + S(A + F)^
6

‡¡◊ËÕ S(t) = °“√√Õ¥™’æ‚¥¬‡©≈’ˬ (average survival) ¢Õß°≈ÿà¡∑¥≈Õß·≈–°≈ÿࡧ«∫§ÿ¡
„π™à«ß‡«≈“ t

(S T ( )t + S c ( ))t
=
2

184 ∫∑∑’Ë 10 «‘∏’§”π«≥¢π“¥µ—«Õ¬à“ß„π°“√»÷°…“·∫∫µà“ßÊ

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