We are planning an Independant trial of a topical treatment for atopic dermatitis using the unmodified SCORAD. In order to assist our power calculation, we need to work out how many points on this scale is clinically meaningful. The sample size is estimated to be 60 to 100.
http://adserver.sante.univ-nantes.fr/Compute.html
This direction may be helpful
Thank you Ricardo for taking the time to look at this.
However, what I am seeking is some examples from colleagues who have used the SCORAD scale in clinical trials as how many points they deemed significantly meaningful. The standard deviation for our calculation has to be obtained from previously published research and I have searches previously published research for over a year, written to many authors but they seem either unable or unwilling to give me the information. This is disheartening when one is trying to conduct research that we will hope will make a positive change in people's lives.
see here for the MCID, :
EASI, (objective) SCORAD and POEM for atopic eczema: responsiveness and minimal clinically important difference
M. E. Schram1, Ph. I. Spuls1, M. M. G. Leeflang2, R. Lindeboom2, J. D. Bos1 andJ. Schmitt3
Article first published online: 27 SEP 2011
DOI: 10.1111/j.1398-9995.2011.02719.x
CORAD is a clinical tool used to assess the extent and severity of eczema (SCORing Atopic Dermatitis). Dermatologists may use this tool before and after treatment to determine whether the treatment has been effective.
Area
To determine extent, the sites affected by eczema are shaded on a drawing of a body. The rule of 9 is used to calculate the affected area (A) as a percentage of the whole body.
Head and neck 9%
Upper limbs 9% each
Lower limbs 18% each
Anterior trunk 18%
Back 18%
1% for genitals.
The score for each area is added up. The total area is 'A', which has a possible maximum of 100%.
Intensity
A representative area of eczema is selected. In this area, the intensity of each of the following signs is assessed as none (0), mild (1), moderate (2) or severe (3).
Redness
Swelling
Oozing / crusting
Scratch marks
Skin thickening (lichenification)
Dryness (this is assessed in an area where there is no inflammation)
The intensity scores are added together to give 'B' (maximum 18).
Thank you Ibrahim for your time on this and willingness to help - I really appreciate it but what you and Ricardo both pointed me to is just the basis of the SCORAD method which I am very familiar with.
The question is How many points on that scale are deemed to make a clinical difference?
Dr. Khoury may I thank you from the bottom of my heart for pointing me to a paper that answers my question.
I appreciate everyone's comments but THANK YOU SO MUCH Dr. Khoury!
Here the website to calculate SCORAD
http://adserver.sante.univ-nantes.fr/Compute.html
Nasser
Thanks Nasser, I am grateful for your time but I know how to calculate SCORAD. My question was not concerning that. It was concerning how to work out the minimum clinically important difference which is quite another matter! My question has now been answered but thank you anyway.