+ Reply to Thread
Results 1 to 5 of 5

Thread: Comparing Treatments for Spinal Cord Injury

  1. #1
    Points: 17, Level: 1
    Level completed: 33%, Points required for next Level: 33

    Posts
    3
    Thanks
    2
    Thanked 0 Times in 0 Posts

    Comparing Treatments for Spinal Cord Injury




    Hi Guys. First post in this forum (actually, in any statistics forum). I am not from an English speaking country, so you may find some grammatical errors.

    Hereís my problem. Iíve tried to search in a lot of places and cant find a specific answer for this question:

    Iím a physician and I work with treatments for spinal cord injury (a lesion caused by spinal trauma). I work with an animal model (rats).

    - I have 5 groups of rats. Each group has 8 rats (I have done de sample size calculation).
    - Each group receives a slightly different treatment (and one is the control group)
    - The rats are monitored by 28 days. At specific days (1,3,7,14,21,28) the rats are evaluated by a scale that goes from 0 to 21 and represent their motor functionality (0 is paraplegic, 21 is normal).

    Now I need to answer this question: Witch treatment is better? What test should I use in SPSS?

    Here is what Iíve made to this point.
    1) ANOVA (with post roc test) between the five groups in each day of evaluation (1,3,7,14,21,28)
    2) Repeated measures ANOVA (with post roc test), which tells me that there is a significant difference between the groups, however, the post hoc test donít show me what I want to see! (It shows me the comparison between the days but I cant see what treatment is better or worse in each day)

    Is there a better test to be done (like a test that compares the curves between the treatments), or should I do the test mentioned above, but in a different (more correct way)?

    Thank you very much!
    I hope I was not too confusing.
    Lucas

  2. #2
    Omega Contributor
    Points: 38,374, Level: 100
    Level completed: 0%, Points required for next Level: 0
    hlsmith's Avatar
    Location
    Not Ames, IA
    Posts
    6,998
    Thanks
    398
    Thanked 1,186 Times in 1,147 Posts

    Re: Comparing Treatments for Spinal Cord Injury

    I don't think this is an Instance for roc. Were treatments randomized? RM ANOVA should work I would think.
    Stop cowardice, ban guns!

  3. The Following User Says Thank You to hlsmith For This Useful Post:

    LucasConzatti (05-03-2015)

  4. #3
    Points: 17, Level: 1
    Level completed: 33%, Points required for next Level: 33

    Posts
    3
    Thanks
    2
    Thanked 0 Times in 0 Posts

    Re: Comparing Treatments for Spinal Cord Injury

    Quote Originally Posted by hlsmith View Post
    I don't think this is an Instance for roc. Were treatments randomized? RM ANOVA should work I would think.
    Hi. Thanks for reply
    My fault about the ďrocĒ. What I meant was ďhocĒ, from ďpost-hoc testsĒ used after ANOVA (like Bonferroni, Tukey etc)
    Yes, treatment was randomized.
    Best regards.
    Lucas

  5. #4
    TS Contributor
    Points: 17,779, Level: 84
    Level completed: 86%, Points required for next Level: 71
    Karabiner's Avatar
    Location
    FC Schalke 04, Germany
    Posts
    2,542
    Thanks
    56
    Thanked 640 Times in 602 Posts

    Re: Comparing Treatments for Spinal Cord Injury

    - I have 5 groups of rats. Each group has 8 rats (I have done de sample size calculation).
    I suppose that allocation to groups was at random.
    2) Repeated measures ANOVA (with post roc test), which tells me that there is a significant difference between the groups, however, the post hoc test donít show me what I want to see! (It shows me the comparison between the days but I cant see what treatment is better or worse in each day)
    It depends by what you mean by "which treatment is better". You
    could just define a time point where you compare groups and
    conclude from that which treatment is better (oneway ANOVA).
    You could define some cutoff for remission or recovery and then
    analyse whether (and when) groups reach this cutoff, using
    Kaplan-Meier-survival analysis. Or you perorm a "mixed" ANOVA
    with the repeated-measures factor "time" and the between-subjects
    factor "group". The interaction of these two factors tells you whether
    changes over time are different between groups.

    With kind regards

    K.

  6. The Following User Says Thank You to Karabiner For This Useful Post:

    LucasConzatti (05-04-2015)

  7. #5
    Points: 17, Level: 1
    Level completed: 33%, Points required for next Level: 33

    Posts
    3
    Thanks
    2
    Thanked 0 Times in 0 Posts

    Re: Comparing Treatments for Spinal Cord Injury


    Quote Originally Posted by Karabiner View Post
    I suppose that allocation to groups was at random.

    It depends by what you mean by "which treatment is better". You
    could just define a time point where you compare groups and
    conclude from that which treatment is better (oneway ANOVA).
    You could define some cutoff for remission or recovery and then
    analyse whether (and when) groups reach this cutoff, using
    Kaplan-Meier-survival analysis. Or you perorm a "mixed" ANOVA
    with the repeated-measures factor "time" and the between-subjects
    factor "group". The interaction of these two factors tells you whether
    changes over time are different between groups.

    With kind regards

    K.
    Thank you very much!
    As soon as I arrive at home i'm going to try this.

    Your help was of an immense value to me!

    Best Regards

    Lucas

+ Reply to Thread

           




Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts






Advertise on Talk Stats