Many researchers and many handbooks referred that cuttoff point of total-item corelations are above .3. But Fiefld (2005) specified that with bigger samples smaller corellation coefficients are acceptable. As Kline (1998) reported that with bigger samples .2 cutoff point may be accepted.
My main question; is there any reference that define the exact sample size of these bigger samples?
Kline, P. (1988) The New Psychometrics: Science, Psychology, and Measurement. London: Routledge.
Field, A. (2005). Discovering statistics using SPSS (2nd ed.). London: Sage Publication.
A sample size calculation that takes into account the effect size should be performed using 0.3 and then with 0.2. There are many free programs that you can perform a power analysis to see if your sample size allows 80% power minimum. I do not think you will find a reference that defines an exact sample size since power analysis is necessary and determined on a case by case basis. Below is a link for a tutorial on issues of type I and II error in determining the level of significance (power).
http://www83.homepage.villanova.edu/richard.jacobs/EDU%208603/lessons/stastical%20power.html
Hi
I agree with Joan, and the following reference is very helpfull
Nunnally J.C. & Bernstein I.H. (1994) Psychometric Theory.
McGraw-Hill, New York.
Good luck
I also had a similar problem in one of previous analysis - I used cuttoff point of total-item corelations above 0.3 regarding available literature (Urbina, S., Essentials of psychological testing. Essentials of behavioral science series. 2004, Hoboken, N.J.: John Wiley & Sons).
Hope it can help you,
Regards
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