Reliability is one of the test used to check the psychometric properties of the tools (e. g. Questionnaire, survey, checklist, etc.). Also, there are other tests such as validity. In my opinion, if your checklist and analysis assess and analyze each item independently you don't need reliability or other test for your tool. However, if you are analyze item as subgroup and total score with a theme (construct) for certain group or for all items then its necessary to check for reliability and validity to enhance the objectivity of your tool. Cronbach alpha, half split analysis are example of these reliability test.

Other important point, if this checklist will be used by more than one rater then it's good to check for interrater reliability test like Cohen's kappa coefficient (κ) to ismeasure inter-rater agreement for qualitative (categorical) items.

Note: may you need kappa test only for each item if you have large number of assessor and may you do not need to go for interns consistency test!

Dear/ Dr. Ahmed

Thank you so much for your valuable answer. In my study I will use a checklist e.g to assess number of outcomes/complications could be appeared based on obesity with pregnancy. is that will be independent items.

Thank you