Name: life table method for survival rates
Uploaded: 2025-01-09T15:14:16.000Z
Duration: 1 min 20 s
Channel: JoVE

يقيم تحليل البقاء على قيد الحياة الوقت حتى حدوث حدث مثل الوفاة أو فشل العلاج. يحلل النهج الاكتواري أو جدول الحياة ، المقتبس من العلوم الاكتوارية ، بيانات البقاء على قيد الحياة.
في سيناريو الدراسة السريرية ، يتم تقسيم المشاركين إلى مجموعات ذات فترات متابعة مختلفة للتركيز على الفترات الحرجة ، مثل السنة الأولى بعد الجراحة عالية الخطورة.
تحسب الطريقة الاكتوارية معدلات البقاء على قيد الحياة على فترات محددة مسبقا ، باستخدام البيانات الكاملة من جميع المشاركين ، بما في ذلك أولئك الذين فقدوا في المتابعة أو الذين ماتوا لأسباب أخرى.
لفهم التأثير على البقاء على قيد الحياة في السنة الأولى ، يتم اشتقاق معدلات البقاء على قيد الحياة لمدة عام واحد عن طريق طرح عدد الوفيات من إجمالي المشاركين والقسمة على الرقم الأصلي.
يتم النظر فقط في المجموعة الفرعية من المرضى الذين تمت ملاحظتهم لمدة عامين كاملين لتقدير البقاء على قيد الحياة لمدة عامين ، مع التركيز على أولئك الذين نجوا في السنة الأولى ثم استمروا في البقاء على قيد الحياة في السنة الثانية.
هذه الطريقة متسقة ، وتساعد في تحديد الاتجاهات طويلة الأجل ، وتقيم فعالية العلاجات أو التدخلات ، مما يوفر أداة قوية لفهم النتائج في البحث الطبي.

النهج الاكتواري

Actuarial Approach

<div style="direction:rtl">النهج الاكتواري، وهو أسلوب إحصائي تم تطويره في الأصل لتقييم مخاطر التأمين على الحياة، يستخدم على نطاق واسع لحساب معدلات البقاء على قيد الحياة في الدراسات السريرية والسكانية. وتأخذ هذه الطريقة في الاعتبار المشاركين الذين فقدوا أثناء المتابعة أو أولئك الذين ماتوا لأسباب لا علاقة لها بالدراسة، مما يضمن تمثيلًا أكثر دقة لاحتمالات البقاء على قيد الحياة. لنتأمل مثال إجراء جراحي عالي الخطورة مع معدل وفيات كبير في مرحلة مبكرة. يتم إجراء دراسة سريرية لمدة عامين، مع التركيز على السنة الأولى الحرجة. يتم تقسيم المشاركين إلى مجموعتين: واحدة يتم متابعتها لمدة عام وأخرى لمدة عامين. يتم تقدير معدلات البقاء على قيد الحياة باستخدام الأسلوب الاكتواري (أو جدول الحياة)، الذي يقسم فترة الدراسة إلى فترات - عادة سنة واحدة. لتوضيح ذلك، افترض أن المجموعة الأولى تبدأ بـ 1000 مريض، يموت منهم 240 مريضًا خلال السنة الأولى. تبدأ المجموعة الثانية أيضًا بـ 1000 مريض، مع 200 حالة وفاة في السنة الأولى و16 حالة وفاة في السنة الثانية. يتم حساب معدل البقاء على قيد الحياة لمدة عام واحد عن طريق طرح العدد الإجمالي للوفيات من حجم المجموعة الأولية وقسمة النتيجة على عدد السكان في البداية: معدل البقاء على قيد الحياة لمدة عام واحد = (2000-240-200)/2000=0.78 أو 78% يمكن تطبيق هذا النهج أيضًا على دراسات النتائج طويلة الأجل، مثل تقييم فعالية علاج السرطان على مر السنين. تستوعب الطريقة الاكتوارية المرضى الذين فقدوا أثناء المتابعة أو الذين ماتوا لأسباب غير ذات صلة، مما يسمح بتحليل قوي للآثار طويلة الأجل. بالنسبة لمعدلات البقاء على قيد الحياة لمدة عامين، يصبح الحساب أكثر دقة. فهو يستخدم الاحتمالية الشرطية، مع مراعاة الأفراد الذين تمت ملاحظتهم لمدة عامين كاملين والذين نجوا من العام الأول فقط. لا يجب أن يتجاوز معدل البقاء على قيد الحياة لمدة عامين معدل العام الواحد ويتم تحديده بضرب احتمال البقاء على قيد الحياة في العام الأول باحتمال البقاء على قيد الحياة في العام الثاني، بشرط البقاء على قيد الحياة في العام الأول: معدل البقاء على قيد الحياة لمدة عامين = 0.78 × 0.98 = 0.7644 أو 76.44٪ هذه الطريقة المتطورة، على الرغم من قوتها، تواجه تحديات مثل بيانات المتابعة غير المكتملة والتسجيل الدقيق للوفيات. وعلى الرغم من هذه القيود، فإنها تظل فعالة بشكل خاص في الدراسات السكانية واسعة النطاق حيث يكون تتبع المشاركين الأفراد غير عملي. من خلال مراعاة احتمالات البقاء على قيد الحياة القائمة على الفواصل الزمنية، يوفر النهج الاكتواري إطارًا موثوقًا به لتحليل البقاء على قيد الحياة في سياقات بحثية متنوعة.</div>

يقيم تحليل البقاء على قيد الحياة الوقت حتى حدوث حدث مثل الوفاة أو فشل العلاج. النهج الاكتواري أو جدول الحياة ، مقتبس من الاكتوارية ...

Education

JoVE Core

Statistics

الإحصائيات

Unit 1

الوحدة الأولى

Survival Analysis

تحليل البقاء

KEY TERMS AND CONCEPTS

المصطلحات والمفاهيم الأساسية

life table method for survival rates

The life table method, also called the actuarial approach, is used to estimate survival rates in clinical and population studies. It began in life insurance, where risk over time must be measured carefully. In health research, it gives a clearer picture of survival when some participants are lost to follow-up or die from causes unrelated to the study.

This method works by dividing the study period into set intervals, usually one year. That makes it useful for tracking outcomes over time, especially in studies with early deaths after a high-risk surgical procedure. In one example, a two-year study follows two groups. One group is observed for one year, and the other is observed for two years.

The one-year survival rate is found from the starting group size and the number of deaths during that year. In the example, 1,000 patients begin in each group. The first group has 240 deaths in the first year, and the second group has 200 deaths in the first year. Using the actuarial calculation, the one-year survival rate is 78%.

The same method can also be used for long-term studies, such as testing how well a cancer treatment works over several years. It accounts for patients who are not followed for the full study or who die from unrelated causes. That makes the survival estimate more realistic when individual tracking is difficult.

Two-year survival uses conditional probability, which means the second year is calculated only for people who survived the first year and were observed for the full two years. In the example, the second-year survival probability is multiplied by the first-year survival probability. The result is 0.78 times 0.98, or 76.44%.

A two-year survival rate should not be higher than the one-year rate. The method is powerful, but it depends on complete follow-up and accurate death records. Even with those limits, it is especially useful in large population studies where following each person closely is not practical.

Life Table Method for Survival Rates

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actuarial approach

The life table method, also called the actuarial approach, is used to estimate survival rates in clinical and population studies. It began in life insurance, where risk over time must be measured carefully. In health research, it gives a clearer picture of survival when some participants are lost to follow-up or die from causes unrelated to the study. This method works by dividing the study period into set intervals, usually one year. That makes it useful for tracking outcomes over time,...

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Left and Right Truncation in Survival Data

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Types of Censoring in Survival Analysis

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key terms and concepts

Learn how the life table method, or actuarial approach, estimates one-year and two-year survival rates while accounting for follow-up losses and unrelated deaths.

Life Table Method for Survival Rates | JoVE K12

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JoVE Core Statistics introduces the concepts and application of the collection, analysis, presentation, and interpretation of data to students. These animated lessons provide an understanding of statistics beneficial to students from a wide range of disciplines. Additionally, the scientist-in-action videos demonstrate the application of related concepts in classical and original research experiments performed in today's laboratories worldwide

Life Table Method for Survival Rates

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