The topic is an important one.

Introduction: club theory was not introduced.

The introduction is too superificial. It could have been more informative if the club theory was introduced and with its relevance to the topic.

The methodology: the query could have retrieved articles with "human environment" in the title. Potentially not retrieving relevant articles without "human environment" in their title. More relevant articles could have been retrieved by searching Title+Abstract+Keywords for the phrase "human environment".

OVID is a good interface and searching three databases-MEDLINE, PyscInfo and Embase is an excellent choice.

How did you identify the themes?