A great example of cultural perspectives being incorporated into the research process is listed on page 641 when the researchers mention how user-involvement helped assess "the approrpiateness of research instruments from a community perspective." This helped to broaden the questions on the questionnaire and interviews, even to the extent of re-wording individual questions. They mention a great example of this being implemented in a study on diabetes; having the patients re-frame questions allowed "researchers to gain invaluable cultural perspectives of diabetes" as it related to social stigma.
The above example on diabetes stands as a great example of how differing perspectives can draw attention to different ideas(beyond the scope of medical researchers). In sum, it creates a greater degree of understanding between the researchers and patients.