Two Psychological Survey Studies: (1) Understanding the Stigma Toward Lung Cancer and (2) Using Research Domain Criteria Project (RDoC) to Predict Remission Rates of Major Depressive Disorder Patients

This dissertation is composed of two psychological survey studies. In the first study, people's negative attitudes toward lung cancer are assessed and discussed. The second topic is about predicting the remission rates of major depressive disorder patients with patients' self-reported questionnaires. In the first topic, I analyzed data from The Lung Cancer Project, an online survey study, to assess both explicit and implicit attitudes expressed by the four participant groups: health care professionals, cancer patients, caregivers and the general public. Negative attitudes toward lung cancer were detected among all these participant groups. I also discovered several demographic factors significantly associated with negative attitudes toward lung cancer. Furthermore, I investigated the association between state-level perceptions of lung cancer (including both explicit and implicit attitudes) and rates of treatment (drug treatment rates or total treatment rates, including surgery, chemotherapy, radiation, and immunotherapy) for lung cancer patients in the corresponding states. In the second topic, existing data from the Combining Medications to Enhance Depression Outcomes (CO-MED) trial were utilized to develop a data-driven method for mapping the behavioral factors to the constructs defined in Research Domain Criteria (RDoC). And I used the defined behavioral factors from CO-MED to discover patient subgroups. In further analysis, I found that the discovered patient subgroups have significantly different remission rates to the antidepressant treatment, which indicates that there are three endo-phenotypes in major depression disorder.