Page 167 - สถิติทางวิทยาศาสตร์สุขภาพ เพื่อการวิจัย

µ—«Õ¬à“ß∑’Ë 9.3

„π°“√‡ª√’¬∫‡∑’¬∫°“√∑”ß“π¢Õߪե §à“ª√‘¡“µ√°“√À“¬„®ÕÕ°‡µÁ¡°”≈—ß (forced

expiratory volume-FEV) √–À«à“ߧπ Ÿ∫∫ÿÀ√’Ë°—∫§π‰¡à Ÿ∫∫ÿÀ√’Ë ®“°√“¬ß“π«‘®—¬∑’˺à“π¡“
æ∫«à“§à“ FEV ¢Õߧπ∑’ˉ¡à Ÿ∫∫ÿÀ√’Ë¡’§à“‡©≈’ˬ 3.43 ·≈–§à“ SD = 0.485 ∂â“°“√ Ÿ∫∫ÿÀ√’Ë
¡“°°«à“ 3 ªï®–∑”„Àâ§à“ FEV ≈¥≈ß√âÕ¬≈– 7 „π°“√»÷°…“¥—ß°≈à“«§«√„™â¢π“¥µ—«Õ¬à“ß

‡∑à“‰√
2 2
®–‰¥â«à“ ˘ = 0.485
°”Àπ¥„Àâ H : ı = ı H : ı > ı
0 Ns s A Ns s
343. ¥ 7
°”Àπ¥„Àâ ı - ı ‡∑à“°—∫√âÕ¬≈– 7 ¢Õß§à“‡©≈’ˬ = = 0.24
1 2
100
°”Àπ¥„Àâ Ò = 0.05 Æ Z = 1.65 Õ”π“®°“√∑¥ Õ∫ 80% Æ Z = 0.84
0.05 0.2
21 65(. + 0 84. ) 2 0 485. 2
n/°≈ÿà¡= 2 = 50.6 ª 51
024.

°“√‡ª√’¬∫‡∑’¬∫ FEV √–À«à“ߧπ Ÿ∫∫ÿÀ√’Ë°—∫§π‰¡à Ÿ∫∫ÿÀ√’˵âÕß„™â¢π“¥µ—«Õ¬à“ß
°≈ÿà¡≈– 51 §π

9.5 °“√§”π«≥¢π“¥µ—«Õ¬à“߇æ◊ËÕ‡ª√’¬∫‡∑’¬∫ —¥ à«π
√–À«à“ߪ√–™“°√ 2 °≈ÿà¡

°“√§”π«≥¢π“¥µ—«Õ¬à“ß«‘∏’π’È„™â„π°“√«‘®—¬‡™‘ß«‘‡§√“–Àå·≈–°“√«‘®—¬‡™‘ß∑¥≈Õß ‡™àπ °“√

∑¥≈Õß«‘∏’°“√√—°…“‚√§ °“√∑¥≈Õß«‘∏’ªØ‘∫—µ‘°“√欓∫“≈ °“√∑¥≈Õß„π™ÿ¡™π °“√À“ªí®®—¬‡ ’ˬß
¢Õß°“√‡°‘¥‚√§ ‡ªìπµâ𠧔∂“¡ß“π«‘®—¬®–‡°’ˬ«¢âÕß°—∫°“√‡ª√’¬∫‡∑’¬∫§à“ —¥ à«π 2 °≈ÿࡥ⫬ ∂‘µ‘ Z
2
Û
À√◊Õ Ÿµ√∑’Ë„™â„π°“√§”π«≥¢π“¥µ—«Õ¬à“ß®–ª√–°Õ∫¥â«¬§à“æ“√“¡‘‡µÕ√å 3 à«π ‡™àπ‡¥’¬«°—π°—∫
°“√‡ª√’¬∫‡∑’¬∫§à“‡©≈’ˬ∑’ËÕ∏‘∫“¬‰«â„πÀ—«¢âÕ 9.4 Ÿµ√∑’Ë„™â„π°“√§”π«≥§◊Õ

2
2(Z a + Z b ) 1 ( p - ) p
n/°≈ÿà¡ = 2
(p T - p C )

‚¥¬∑’Ë p=(p + p )/2
T C
p = —¥ à«π„π°≈ÿà¡∑¥≈Õß
T
p = —¥ à«π„π°≈ÿࡧ«∫§ÿ¡
C
n= ¢π“¥µ—«Õ¬à“ßµàÕ°≈ÿà¡

166 ∫∑∑’Ë 9 °“√§”π«≥¢π“¥µ—«Õ¬à“ß·≈–Õ”π“®°“√∑¥ Õ∫

∫∑∑’Ë 9 166 29/7/09, 5:33 PM