hi, this guide to analyzing changes in prevalence rates over time with complex survey data might also help? thanks
http://asdfree.com/trend-analysis-of-complex-survey-data.html On Wed, Jan 17, 2024, 9:15 AM John Fox <j...@mcmaster.ca> wrote: > Dear Md Kamruzzaman, > > To answer your second question first, you could just use the svychisq() > function. The difference-of-proportion test is equivalent to a chisquare > test for the 2-by-2 table. > > You don't say how you computed the confidence intervals for the two > separate proportions, but if you have their standard errors (and if not, > you should be able to infer them from the confidence intervals) you can > compute the variance of the difference as the sum of the variances > (squared standard errors), because the two proportions are independent, > and from that the confidence interval for their difference. > > I hope this helps, > John > -- > John Fox, Professor Emeritus > McMaster University > Hamilton, Ontario, Canada > web: https://www.john-fox.ca/ > > On 2024-01-16 10:21 p.m., Md. Kamruzzaman wrote: > > [You don't often get email from mkzama...@gmail.com. Learn why this is > important at https://aka.ms/LearnAboutSenderIdentification ] > > > > Caution: External email. > > > > > > Hello Everyone, > > I was analysing big survey data using survey packages on RStudio. Survey > > package allows survey data analysis with the design effect.The survey > > package included functions for all other statistical analysis except > > two-proportion z tests. > > > > I was trying to calculate the difference in prevalence of Diabetes and > > Prediabetes between the year 2011 and 2017 (with 95%CI). I was able to > > calculate the weighted prevalence of diabetes and prediabetes in the Year > > 2011 and 2017 and just subtracted the prevalence of 2011 from the > > prevalence of 2017 to get the difference in prevalence. But I could not > > calculate the 95%CI of the difference in prevalence considering the > weight > > of the survey data. > > > > I was also trying to see if this difference in prevalence is > statistically > > significant. I could do it using the simple two-proportion z test without > > considering the weight of the sample. But I want to do it considering the > > weight of the sample. > > > > > > Example: Prevalence of Diabetes: > > 2011: 11.0 (95%CI > > 10.1-11.9) > > 2017: 10.1 (95%CI > > 9.4-10.9) > > Diff: 0.9% (95%CI: > ??) > > Proportion Z test P > > Value: ?? > > Your cooperation will be highly appreciated. > > > > Thanks in advance. > > > > With Regards > > > > *--------------------------------* > > > > *Md Kamruzzaman* > > > > *PhD **Research Fellow (**Medicine**)* > > Discipline of Medicine and Centre of Research Excellence in Translating > > Nutritional Science to Good Health > > Adelaide Medical School | Faculty of Health and Medical Sciences > > The University of Adelaide > > Adelaide SA 5005 > > > > [[alternative HTML version deleted]] > > > > ______________________________________________ > > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > > https://stat.ethz.ch/mailman/listinfo/r-help > > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > > and provide commented, minimal, self-contained, reproducible code. > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
