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 I am doing crossover design to compare the effect of indoor and outdoor running on weightloss among obese people. I'm having a problem in the statistical analysis which, I didn't really know the right way to analyze it in SPSS. Do I use the paired sample t-test? How? Sorry, I'm still in the learning process and getting a little help from you guys should be great. Thank you in advance.
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 Administrator Do you mean a simple 2x2 design like this? Group 1:  Indoor first, outdoor second Group 2:  Outdoor first, indoor second If so, I would structure the data file like this: ID  Order  Indoor  Outdoor 1     1          Y1         Y2 2     2          Y1         Y2 3     1          Y1         Y2 4     2          Y1         Y2 etc Then, I would use GLM-Repeated Measures with Location (indoor v outdoor) as the within-Ss factor and Order as the between-Ss factor.  Your main questions, I assume, are whether there is a difference between indoor and outdoor, and whether it depends on the order in which they occurred.  Those questions are addressed by the F-tests for Location and the Order*Location interaction.   Finally, note that there is a lot of variation in how people conceptualize and describe even this simple design--e.g., in some fields, people would talk about the "period" effect rather than the order, as I have done here.  Jerry Dallal talks about this in his notes on crossover studies:   http://www.jerrydallal.com/LHSP/crossovr.htmYou'll want to use the conceptual approach that is familiar to people in your field.   HTH. joannerachell wrote I am doing crossover design to compare the effect of indoor and outdoor running on weightloss among obese people. I'm having a problem in the statistical analysis which, I didn't really know the right way to analyze it in SPSS. Do I use the paired sample t-test? How? Sorry, I'm still in the learning process and getting a little help from you guys should be great. Thank you in advance. -- Bruce Weaver bweaver@lakeheadu.ca http://sites.google.com/a/lakeheadu.ca/bweaver/"When all else fails, RTFM." NOTE: My Hotmail account is not monitored regularly. To send me an e-mail, please use the address shown above.
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 Thank you guys. Yeap it is simple 2x2 design and I'm using the design for the first time so I really didn't know. On May 13, 2015 9:36 PM, "Bruce Weaver [via SPSSX Discussion]" <[hidden email]> wrote: Do you mean a simple 2x2 design like this? Group 1:  Indoor first, outdoor second Group 2:  Outdoor first, indoor second If so, I would structure the data file like this: ID  Order  Indoor  Outdoor 1     1          Y1         Y2 2     2          Y1         Y2 3     1          Y1         Y2 4     2          Y1         Y2 etc Then, I would use GLM-Repeated Measures with Location (indoor v outdoor) as the within-Ss factor and Order as the between-Ss factor.  Your main questions, I assume, are whether there is a difference between indoor and outdoor, and whether it depends on the order in which they occurred.  Those questions are addressed by the F-tests for Location and the Order*Location interaction.   Finally, note that there is a lot of variation in how people conceptualize and describe even this simple design--e.g., in some fields, people would talk about the "period" effect rather than the order, as I have done here.  Jerry Dallal talks about this in his notes on crossover studies:   http://www.jerrydallal.com/LHSP/crossovr.htmYou'll want to use the conceptual approach that is familiar to people in your field.   HTH. joannerachell wrote I am doing crossover design to compare the effect of indoor and outdoor running on weightloss among obese people. I'm having a problem in the statistical analysis which, I didn't really know the right way to analyze it in SPSS. Do I use the paired sample t-test? How? Sorry, I'm still in the learning process and getting a little help from you guys should be great. Thank you in advance. -- Bruce Weaver [hidden email] http://sites.google.com/a/lakeheadu.ca/bweaver/"When all else fails, RTFM." NOTE: My Hotmail account is not monitored regularly. To send me an e-mail, please use the address shown above. If you reply to this email, your message will be added to the discussion below: http://spssx-discussion.1045642.n5.nabble.com/Crossover-design-in-SPSS-tp5729553p5729554.html To unsubscribe from Crossover design in SPSS, click here. NAML
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 I found this to be a good article that describes what Bruce is suggesting. I was able to input the data in the article and replicate the results. http://ligarto.org/rdiaz/Papers/cross-over-animal-behaviour.pdf