Question

Be wary of including items in a composite measure that are not related to one another empirically.

b. you should probably drop any item that is not related to several other items in your composite measure.
c. if items are unrelated it is unlikely that they measure the same variable.
d. you must check the bivariate correlations between all items that you plan to include in your composite measure.
e. face validity does not need to be considered.

Answer 1

Face validity is a simple form of validity where one applies a superficial and subjective assessment of whether or not ones study or test measures what it is supposed to measure. In this case,i think the statement face validity does not need to be considered is false. Face validity unlike construct validity and content validity is considered to be superficial measure of validity as it is not about  what the measurement procedure measure, but what it appears to measure.