I am planning a fixed-sequence 2-treatment (placebo followed by drug) crossover study. There is a Placebo run-in period of 15 days. Placebo is the control and has no effect on BP. The aim is to prove the efficacy of the medicine for treatment of blood pressure. I take one measurement while on placebo (A) (control) for one month. And then treatment is given for 1 year. Measurements are taken after 3 months and 9 months of treatment. After this, dose of medicine is tapered by 30% for one month, BP is recorded again at 10 months and the minimum dose required to maintain BP is given till 1 year and the final measurement is taken. Note is made about the experience of the recording nurses-junior or senior (>5 years’ experience). BP recordings are made in A/C and Non-A/C rooms for studying the effect of ambient temperature. There is no funding for the study. The trial is a double-blind study till the 3rd month's data collection and open-label after that because of practical difficulties in blinding the medicine. This fixed sequence 3-period 2-treatment (AB) crossover design study is done on about 150 patients. The hypothesis is that medicine normalizes BP, Non-A/C rooms increase BP and senior nurses’ recordings show lower readings.

  • $\begingroup$ You created three tags here, could you please edit their descriptions to provide guidance in their usage? It's not clear to me from their tag names alone what they mean. $\endgroup$
    – Firebug
    May 17 '20 at 16:32
  • $\begingroup$ I am a beginner in statistics. I am sorry, I could not understand your query. I could not find a way to edit the tag descriptions. Because no patient will agree to stop the drug when there is improvement, I had to make it fixed-sequence. Because there is long term additional effect appearing after 9 months, I thought of taking an additional recording of measurements at the end of 1 year treatment. I will be eager to provide any additional clarifications, is required. $\endgroup$
    – DrWho
    May 18 '20 at 3:33
  • $\begingroup$ Nah, you're good. I came here through the moderating tools because I saw the new tags. You can keep them if you think there are no good tags that convey the sense of your question (keep in mind that it doesn't help people to see your question though, because they have no other questions in them and so no followers). It's just that, reading their names, I couldn't judge what they refer to and if there are synonym tags to merge perhaps. But it's fine, don't worry :) $\endgroup$
    – Firebug
    May 18 '20 at 13:59
  • $\begingroup$ Thank you. I thought somebody would answer in a few minutes. I am surprised at the time being taken. $\endgroup$
    – DrWho
    May 19 '20 at 2:35
  • $\begingroup$ Which hypothesis do you want to test with this experiment? What kind of noise/variations do you expect? What is the point of the placebo? What is your theory/hypothesis for presence/absence of the medicin? $\endgroup$ Jun 14 '20 at 12:24

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