{"id":496,"date":"2020-02-05T20:31:17","date_gmt":"2020-02-05T17:31:17","guid":{"rendered":"https:\/\/www.aciltipakademisi.org\/?p=496"},"modified":"2021-11-16T04:10:02","modified_gmt":"2021-11-16T01:10:02","slug":"bulgularin-degeri-kirilganlik-indeksi-fragility-index","status":"publish","type":"post","link":"https:\/\/tatd.org.tr\/atak\/2020\/02\/05\/bulgularin-degeri-kirilganlik-indeksi-fragility-index\/","title":{"rendered":"Bulgular\u0131n De\u011feri: K\u0131r\u0131lganl\u0131k \u0130ndeksi (Fragility index)"},"content":{"rendered":"\n

K\u0131r\u0131lganl\u0131k indeksi<\/strong> Bayes kuram\u0131n\u0131 temel alarak olu\u015fturulmu\u015f bir indekstir. Temel olarak ikili sonu\u00e7lar\u0131n bildirildi\u011fi ve 2×2 (4 g\u00f6zl\u00fc) tablo olu\u015fturulan her durumda kullan\u0131labilir. \u00c7al\u0131\u015fmada, beklenen sonucun ger\u00e7ekle\u015fmedi\u011fi vakalar\u0131n ka\u00e7\u0131nda sonu\u00e7 ger\u00e7ekle\u015fseydi istatistiksel anlaml\u0131l\u0131k kaybolurdu sorusunun yan\u0131t\u0131d\u0131r.<\/p>\n\n\n\n

A\u015fa\u011f\u0131daki 2×2 tabloyu de\u011ferlendirelim: 150 dene\u011fin yer ald\u0131\u011f\u0131 bir \u00e7al\u0131\u015fmada (g\u00f6zlemsel ya da randomize kontroll\u00fc olabilir) 100 dene\u011fe etkisi de\u011ferlendirilen uygulama yap\u0131lm\u0131\u015f (ila\u00e7, ameliyat ya da farkl\u0131 bir etki olabilir). Bu 100 denekten 90\u2019\u0131nda (%90) ba\u015far\u0131l\u0131 sonu\u00e7 elde edilmi\u015f. Herhangi bir uygulama yap\u0131lmayan 50 ki\u015fiden ise 15\u2019inde (%30) ba\u015far\u0131 g\u00f6zlenmi\u015f. Bu iki oran aras\u0131ndaki fark (%90 ile %30) istatistiksel olarak anlaml\u0131 bulunmu\u015f.<\/p>\n\n\n\n

Peki, yukar\u0131daki tan\u0131ma g\u00f6re k\u0131r\u0131lganl\u0131k indeksi ka\u00e7t\u0131r?<\/strong><\/p>\n\n\n\n

\"\u015eekil<\/a>
\u015eekil 1. \u0130statistiksel anlaml\u0131 fark tespit edilen \u00f6rnek 2×2 tablo<\/figcaption><\/figure><\/div>\n\n\n\n

Bunun i\u00e7in, beklenen sonucun ger\u00e7ekle\u015fmedi\u011fi vakalar\u0131n say\u0131s\u0131n\u0131 birer birer azalt\u0131p, sonu\u00e7 ger\u00e7ekle\u015fenlerin say\u0131s\u0131n\u0131 birer birer artt\u0131r\u0131yoruz. Halihaz\u0131rda vaka gurubunda sonu\u00e7 ger\u00e7ekle\u015fenler zaten %90\u2019da oldu\u011fundan aradaki fark\u0131 azaltmak i\u00e7in bu art\u0131rma i\u015flemini az olan sonu\u00e7 ger\u00e7ekle\u015fme oran\u0131 %30 olan kontrol grubunda yap\u0131yoruz. Kontrol grubunda sonu\u00e7 ger\u00e7ekle\u015fen ki\u015fi say\u0131s\u0131n\u0131 15\u2019den 16\u2019ya \u00e7\u0131kar\u0131rken, sonu\u00e7 ger\u00e7ekle\u015fmeyen ki\u015fi say\u0131s\u0131n\u0131 35\u2019den 34\u2019e d\u00fc\u015f\u00fcr\u00fcp tekrar p de\u011ferini hesapl\u0131yoruz. Bu i\u015flemi p de\u011ferinin anlaml\u0131 kabul edilmedi\u011fi e\u015fik de\u011ferin \u00fczerine \u00e7\u0131kana kadar devam ediyoruz.<\/p>\n\n\n\n

A\u015fa\u011f\u0131daki tabloda g\u00f6r\u00fcld\u00fc\u011f\u00fc \u00fczere art\u0131k istatistiksel anlaml\u0131 fark olmad\u0131\u011f\u0131na kanaat getirece\u011fimiz p=0,08 de\u011ferine 24 ki\u015fide sonucun de\u011fi\u015ftirilmesi ile ula\u015f\u0131ld\u0131\u011f\u0131n\u0131 tespit edebiliriz. 50 ki\u015filik kontrol grubunda 15 vakada ba\u015far\u0131l\u0131 sonu\u00e7 g\u00f6zlenmi\u015f ve bu sebeple de vaka grubu kontrol grubundan daha iyi \u00e7\u0131km\u0131\u015ft\u0131. E\u011fer kontrol grubunda 24 ki\u015fide daha ba\u015far\u0131l\u0131 sonu\u00e7 g\u00f6zlenseydi (neredeyse 2,5 kat\u0131) aradaki fark anlams\u0131z olacakt\u0131. Burada buldu\u011fumuz 24 say\u0131s\u0131 k\u0131r\u0131lganl\u0131k indeksidir. Bu say\u0131y\u0131 elle tabii ki hesaplam\u0131yoruz. http:\/\/fragilityindex.com\/<\/a> adresinde 4 g\u00f6zl\u00fc tablodaki say\u0131lar\u0131 girerek kolayl\u0131kla k\u0131r\u0131lganl\u0131k indeksini hesaplayabiliriz.<\/p>\n\n\n\n

\"\u015eekil<\/a>
\u015eekil 2. K\u0131r\u0131lganl\u0131k indeksini tespit etti\u011fimiz nokta<\/figcaption><\/figure><\/div>\n\n\n\n

Bu \u00f6rnekte buldu\u011fumuz k\u0131r\u0131lganl\u0131k indeksi olan 24, kontrol grubumuzun yar\u0131s\u0131nda sonucunun de\u011fi\u015fmesi manas\u0131na gelece\u011finden olduk\u00e7a y\u00fcksektir ve buldu\u011fumuz sonucun g\u00fcvenilir oldu\u011funu g\u00f6sterir.<\/p>\n\n\n\n

Bir \u00f6rnek: NINDS \u00c7al\u0131\u015fmas\u0131<\/h4>\n\n\n\n

1995 y\u0131l\u0131nda NEJM dergisinde yay\u0131nlanan ve Akut iskemik inmede tPA tedavisiyle ciddi kanama oran\u0131n\u0131n y\u00fcksek oldu\u011funu g\u00f6steren \u00e7al\u0131\u015fmalara kar\u015f\u0131 kurgulanan NINDS \u00e7al\u0131\u015fmas\u0131n\u0131 ele alal\u0131m. NINDS \u00e7al\u0131\u015fmas\u0131n\u0131n orjinal sonu\u00e7lar\u0131n\u0131 a\u015fa\u011f\u0131daki tablo ve \u015fekillerde g\u00f6rebilirsiniz.<\/p>\n\n\n\n

\"\u015eekil<\/a>
\u015eekil 3. NINDS \u00e7al\u0131\u015fmas\u0131n\u0131n orjinal sonu\u00e7lar\u0131<\/figcaption><\/figure><\/div>\n\n\n\n

Bu \u00e7al\u0131\u015fmada tPA uygulanan ve uygulanmayan inme hastalar\u0131n\u0131n y\u00fcz g\u00fcld\u00fcr\u00fcc\u00fc sonu\u00e7 oranlar\u0131 4 farkl\u0131 skala ile de\u011ferlendirilmi\u015f. Yazarlar ger\u00e7ek hasta say\u0131lar\u0131n\u0131 ayr\u0131nt\u0131s\u0131yla yaz\u0131da vermeyi tercih etmemi\u015f ama \u00fcreticinin internet sitesinde ve Avrupa \u0130la\u00e7 Birli\u011fi kay\u0131tlar\u0131ndan halka a\u00e7\u0131k \u015fekilde ula\u015fmak m\u00fcmk\u00fcn. Bu say\u0131lar\u0131 elde etti\u011fimizde a\u015fa\u011f\u0131daki tabloyu olu\u015fturabiliyoruz:<\/p>\n\n\n\n

\"\u015eekil<\/a>
\u015eekil 4. NINDS \u00e7al\u0131\u015fmas\u0131nda tedavi gruplar\u0131n\u0131n Barthel \u0130ndeksine g\u00f6re sonlan\u0131mlar\u0131n\u0131n kar\u015f\u0131la\u015ft\u0131r\u0131lmas\u0131<\/figcaption><\/figure><\/div>\n\n\n\n

Bu tabloya g\u00f6re tPA verilen (alan) 168 hastadan 84\u2019\u00fc iyi (kabul edilebilir) bir \u015fekilde sonlanm\u0131\u015f iken (%50), plasebo verilen (alan) 165 hastadan 62\u2019sinde iyi sonu\u00e7lar g\u00f6zlenmi\u015f (%37.5). \u00c7al\u0131\u015fmac\u0131lar %50\u2019nin %37.5\u2019den istatistiksel olarak anlaml\u0131 derecede y\u00fcksek oldu\u011fundan yola \u00e7\u0131karak [highlight color=”yellow”]\u201csemptomatik intrakranyal kanama insidans\u0131nda art\u0131\u015fa ra\u011fmen, iskemik inmenin ilk 3 saatinde uygulanan IV tPA tedavisi 3 ayl\u0131k klinik sonlan\u0131mlar\u0131 iyile\u015ftirmektedir\u201d[\/highlight] yorumunu yapm\u0131\u015flar.<\/p>\n\n\n\n

Peki, Acil T\u0131pta inmeye yakla\u015f\u0131m\u0131m\u0131z\u0131 k\u00f6k\u00fcnden de\u011fi\u015ftiren bu \u00e7al\u0131\u015fman\u0131n k\u0131r\u0131lganl\u0131k indeksi ka\u00e7t\u0131r?  <\/strong><\/p>\n\n\n\n

http:\/\/fragilityindex.com\/<\/a> adresine gidip say\u0131lar\u0131 girdi\u011fimizde [highlight color=”yellow”]K\u0131r\u0131lganl\u0131k \u0130ndeksinin sadece 3 vaka oldu\u011funu<\/strong>[\/highlight] g\u00f6r\u00fcyoruz.<\/p>\n\n\n\n

Peki, sizce kontrol grubunda 62 yerine 65 ki\u015finin iyi sonlan\u0131ma eri\u015fmesiyle sonucu anlams\u0131z hale gelecek bu \u00e7al\u0131\u015fmaya g\u00fcvenmeli miyiz?<\/strong><\/p>\n\n\n\n

Ne yaz\u0131k ki hay\u0131r.<\/p>\n\n\n\n

Peki, di\u011fer \u00e7al\u0131\u015fmalar\u0131n sonu\u00e7lar\u0131 neler?<\/strong><\/p>\n\n\n\n

\u00c7o\u011fu \u00e7al\u0131\u015fma asl\u0131nda trombolitiklerin fayda sa\u011flamad\u0131\u011f\u0131n\u0131 hatta baz\u0131lar\u0131 da zarar verdi\u011fini g\u00f6stermi\u015f.<\/p>\n\n\n\n

E o zaman, 95 y\u0131l\u0131ndan beri inme hastalar\u0131na bo\u015funa m\u0131 trombolitik veriyoruz?<\/strong><\/p>\n\n\n\n

\u00d6zel se\u00e7ilmi\u015f bir hasta grubunda faydal\u0131 olabileceklerine ben hala inan\u0131yorum. Ama bu hasta grubu kesinlikle NINDS ya da di\u011fer \u00e7al\u0131\u015fmalar\u0131n hasta pop\u00fclasyonu de\u011fil.<\/p>\n\n\n\n

\u00d6zetle, \u00e7al\u0131\u015fman\u0131z\u0131n sonu\u00e7lar\u0131n\u0131 bildirirken k\u0131r\u0131lganl\u0131k indeksinizi de bir hesaplay\u0131n. E\u011fer \u00e7ok d\u00fc\u015f\u00fck bir indeksiniz varsa yorumlar\u0131n\u0131zda tutucu olman\u0131z sizin faydan\u0131za olacakt\u0131r. Hakemlerinizin yaz\u0131n\u0131z\u0131 de\u011ferlendirirken k\u0131r\u0131lganl\u0131k indeksi, instabilite indeksi gibi say\u0131lar\u0131 hesaplayaca\u011f\u0131n\u0131 unutmay\u0131n.<\/p>\n\n\n\n

\"\u015eekil<\/a>
\u015eekil 5. Fragilityindex.com sitesinden NINDS \u00e7al\u0131\u015fma sonu\u00e7lar\u0131n\u0131n d\u00f6k\u00fcm\u00fc<\/figcaption><\/figure><\/div>\n\n\n\n
Kaynaklar<\/h5>\n\n\n\n

1 – Fragilityindex.com<\/p>\n","protected":false},"excerpt":{"rendered":"

K\u0131r\u0131lganl\u0131k indeksi Bayes kuram\u0131n\u0131 temel alarak olu\u015fturulmu\u015f bir indekstir. Temel olarak ikili sonu\u00e7lar\u0131n bildirildi\u011fi ve 2×2 (4 g\u00f6zl\u00fc) tablo olu\u015fturulan her durumda…<\/p>\n","protected":false},"author":1561,"featured_media":497,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"inline_featured_image":false,"_lmt_disableupdate":"","_lmt_disable":"","footnotes":""},"categories":[21,10014],"tags":[],"class_list":["post-496","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-istatistik-yazilari","category-akademik-blog-yazisi"],"acf":[],"_links":{"self":[{"href":"https:\/\/tatd.org.tr\/atak\/wp-json\/wp\/v2\/posts\/496","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/tatd.org.tr\/atak\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/tatd.org.tr\/atak\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/tatd.org.tr\/atak\/wp-json\/wp\/v2\/users\/1561"}],"replies":[{"embeddable":true,"href":"https:\/\/tatd.org.tr\/atak\/wp-json\/wp\/v2\/comments?post=496"}],"version-history":[{"count":0,"href":"https:\/\/tatd.org.tr\/atak\/wp-json\/wp\/v2\/posts\/496\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/tatd.org.tr\/atak\/wp-json\/wp\/v2\/media\/497"}],"wp:attachment":[{"href":"https:\/\/tatd.org.tr\/atak\/wp-json\/wp\/v2\/media?parent=496"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/tatd.org.tr\/atak\/wp-json\/wp\/v2\/categories?post=496"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/tatd.org.tr\/atak\/wp-json\/wp\/v2\/tags?post=496"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}