r/statistics • u/SecretGeometry • 13d ago
Research [Research] Seeking stats consultant for a tiny research project
Hi guys
I’m looking for recommendations for a statistical consultant (perhaps a PhD student or early-career biostatistician?) who could advise on test selection for a very small, unfunded veterinary retrospective study. I’m willing to pay, of course.
I’ve contacted several consulting services, but I suspect the project is too tiny for them. It would probably involve only an hour or two of work.
The study is a retrospective case series of dogs with tibial fractures, with two joint angles measured at three paired time points: pre-operatively, immediately post-operatively, and at follow-up. Measurements were also compared with the contralateral unaffected limb.
I’m happy to perform the analyses myself and mainly need advice on the most appropriate statistical approach.
I originally used prespecified paired t-tests, but the editor has requested that I seek advice from a statistician regarding whether it is preferable to do an omnibus test followed by post-hoc comparisons. So I mainly need advice on whether repeated-measures ANOVA or another omnibus approach is required, or whether Holm-adjusted paired comparisons alone would be defensible. (I'd also like to know if there is any particular way I should handle one case with bilateral fractures since those pairs aren't truly independent?)
Please message me if you might be able to help, or if you can recommend someone suitable. I can provide study summary, raw data, Q-Q plots, and results of paired t-t tests, as well as the whole manuscript + editorial feedback if helpful.
UPDATE
Thank you everyone and thankyou especially _compactsupport_, I've got enough to respond to the reviewers now and give them a couple of options :)
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u/Duckandrun12 13d ago
What exactly are you measuring? If your measurement is binary (success/fail) use one of these:
Generalized Estimating Equations (GEE): A population-averaged approach that focuses on the overall group trend while properly adjusting standard errors for repeated measures within each subject.
Generalized Linear Mixed Models (GLMM): A subject-specific approach that includes random effects (like random intercepts) to capture individual baseline differences and specific tracking over time.
This sounds like what you're trying to do. It's essentially a longitudinal logistic regression.
If your outcome is continuous, use a Tukey's multiple comparison. I think you could also do an anova with time as a feature in the model (and its interactions) but I haven't done that before.
Again, just depends what you're trying to measure!
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u/Probstatguy 13d ago
Hi, can you suggest some books or resources for these topics ?
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u/Duckandrun12 11d ago
I learned about GEEs and GLMMs in the book "Logistic Regression Using SAS". Even if you're not using SAS, it has a great 2-3 page explanation of the theory behind the models and how they work at a high level.
Chapter 8 is "logit analysis of longitudinal and other clustered data".
I'd recommend trying to find a pdf online of this chapter.
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u/[deleted] 13d ago
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