Confidence intervals for rate ratios between geographic units

نویسندگان

  • Li Zhu
  • Linda W Pickle
  • James B Pearson
چکیده

BACKGROUND Ratios of age-adjusted rates between a set of geographic units and the overall area are of interest to the general public and to policy stakeholders. These ratios are correlated due to two reasons-the first being that each region is a component of the overall area and hence there is an overlap between them; and the second is that there is spatial autocorrelation between the regions. Existing methods in calculating the confidence intervals of rate ratios take into account the first source of correlation. This paper incorporates spatial autocorrelation, along with the correlation due to area overlap, into the rate ratio variance and confidence interval calculations. RESULTS The proposed method divides the rate ratio variances into three components, representing no correlation, overlap correlation, and spatial autocorrelation, respectively. Results applied to simulated and real cancer mortality and incidence data show that with increasing strength and scales in spatial autocorrelation, the proposed method leads to substantial improvements over the existing method. If the data do not show spatial autocorrelation, the proposed method performs as well as the existing method. CONCLUSIONS The calculations are relatively easy to implement, and we recommend using this new method to calculate rate ratio confidence intervals in all cases.

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

بررسی میزان های بروز عوارض ریوی و خطر نسبی عوامل موثر بر آن در مصدومین شیمیایی گاز خردل جنگ تحمیلی عراق علیه ایران

Sulfur mustard is the most widely used chemical agent in the Iran-Iraq war .In a retrospective cohort study of 1337 soldiers with a history of sulfur mustard exposure, factors such as age, smoking habits, number of exposure episodes and the use of gas masks were determined, together with an assessment of their relationship with the occurrence of long-term pulmonary complications. The models sug...

متن کامل

Exploring associations between residential location and breast cancer incidence in a case-control study.

Locating geographic hot spots of cancer may lead to new causal hypotheses and ultimately to new knowledge of cancer-causing factors. The Cape Cod region of Massachusetts has experienced elevated incidence of breast cancer compared with statewide averages. The origins of the excess remain largely unexplained, even after the Upper Cape Cod Cancer Incidence Study investigated numerous potential en...

متن کامل

Bioequivalence Studies of Two Formulations of Baclofen Tablet in Healthy Volunteers

The relative bioavailability of the test (generic) product 2 × 25 mg baclofen tablets, with respect to the reference product, Lioresal® 2 × 25 mg tablets (baclofen; Squibb) was determined in a single-blind, single dose, randomised, crossover study. The mean values for the variable Cmax were 737.6 ng/ml for the reference and 739.5 ng/ml for the test product. The mean values for the variable AUC ...

متن کامل

Bioequivalence Studies of Two Formulations of Baclofen Tablet in Healthy Volunteers

The relative bioavailability of the test (generic) product 2 × 25 mg baclofen tablets, with respect to the reference product, Lioresal® 2 × 25 mg tablets (baclofen; Squibb) was determined in a single-blind, single dose, randomised, crossover study. The mean values for the variable Cmax were 737.6 ng/ml for the reference and 739.5 ng/ml for the test product. The mean values for the variable AUC ...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره 15  شماره 

صفحات  -

تاریخ انتشار 2016