Part 1:
1. Choose a paper describing the development or validation of a measure of relevance in health disparities research (please give the full citation and/or upload the paper if that's possible).
Hong, H. C., & Min, A. (2018). Translation and Validation of the Korean Version of the Revised Health Care System Distrust Scale (HCSD-K) in Korean American Women. International journal of environmental research and public health, 15(9), 1964. https://ucsf.idm.oclc.org/login?url=https://doi.org/10.3390/ijerph15091964
The quick pubmed link to the full article is: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6163931/
2. What was the definition of the construct?
The authors adapted their definition of "trust" from the 1995 paper by Mayer et al. entitled "An Integrative Model of Organizational Trust." Mayer et al had defined trust as "the willingness of a party to be vulnerable to the actions of another party based on the expectation that the other will perform a particular action important to the trustor, irrespective of the ability to monitor or control that other party."
3. How did the authors provide evidence on the validity of the measure? Could you think of additional approaches to validating the measure?
First the authors performed a confirmatory factor analysis (CFA) to assess whether the two factors of the original Revised HCSD scale, which is in English, could adequately describe the data of the Korean version (HCSD-K). The two factors were 1) competence distrust (“perception that the entity is (not) capable of doing what is needed”) and values distrust (“perception that the entity (does not) wants to do what is needed”). The CFA showed a two-factor structure with a strong fit. Next, the authors assessed discriminant validity by comparing the average variance extracted value of each latent construct with the shared variance between constructs. They then assessed convergent validity via Pearson’s correlation coefficients: they correlated scores obtained from the HCSD-K, Perceived Discrimination in Health Care, and Trust in Physician scales. I think that they were very thorough in their validation techniques, as they compared their measure (the HCSD-K) to the preexisting, well-established scales pertaining to measuring patient trust.
4. How did the authors provide evidence on the reliability of the measure? Could you think of additional approaches to evaluating the reliability of the measure?
The authors assessed reliability using Cronbach’s alpha coefficient, which estimates the reliability of psychometric tests. I found an alternative test called congeneric reliability ("rho C") that could have also been used to evaluate reliability in this study; it is another tool for assessing reliability in psychometric tests. Cronbach's alpha relies on the assumption that all "factor loadings" are equal which is rarely true in the real world, so it tends to underestimate reliability. Congeneric reliability does not use this assumption so that is one benefit of using it over Cronbach's alpha.
5. Describe the implications of a lack of measurement validity or reliability for future research applications.
The overarching goal of this study was to validate the HCSD-K so that it can be used in research regarding trust in the healthcare system as a variable that influences racial disparities in health and health care. If this instrument lacked validity or reliability, then researchers would not be able to perform studies that surveyed Korean-American women whose primary language is Korean (e.g. immigrant women). Studies would have to be limited to patients who were fluent in English and could read the Revised HCSD scale survey.
Part 2:
1. Find a paper describing a health disparity (please give the full citation or, even better, upload the paper so everyone else can look at it too)
Green TL, Bodas MV, Jones HA, Masho SW, Hagiwara N. Disparities in Self-Reported Prenatal Counseling: Does Immigrant Status Matter?. J Community Health. 2018;43(5):864–873. doi:10.1007/s10900-018-0495-z
The quick link to the full article is: https://link.springer.com/article/10.1007%2Fs10900-018-0495-z
2. Summarize the construct and measurement of the dimension of disparity (e.g., racial inequalities?, SES inequalities?) and the outcome measured (e.g., self-rated health).
The construct is pregnancy-related knowledge among women who are pregnant or planning to become pregnant. The dimension of disparity is maternal immigration status (whether the mother was born outside of the United States). The outcome measured is self-reported receipt of prenatal counseling, which includes topics such as diet, tobacco and alcohol use, medication use, breastfeeding, baby development, and early labor.
3. What is the evidence for the validity and reliability of the measures?
The researchers interviewed mothers 9 months after they had given birth, and asked specific questions such as whether she had gotten advice from her prenatal provider regarding: "(1) what to eat (2) smoking (3) drinking (4) safe medication (5) baby development (6) signs of early labor and (7) breastfeeding." They based these questions of off previously published literature on the "determinants of prenatal care content." The researches then included an alternate measure of English proficiency (whether a mother had been interviewed in a non-English language) to see whether language used during interview impacted the results.
4. What is the reference category used for the disparity measure (ie, who is the comparison group)? Why does this reference category make sense (or not) for this research question?
The reference category for maternal immigrant status is mothers born in the United States. This makes sense because maternal immigrant status is a binary category, and the authors' research questions is about whether being born outside of the U.S. impacts one's receipt of prenatal counseling.
5. How is the disparity quantified or measured? Is this an absolute or relative measure or are both provided? Describe which type of measure you would prefer for this research area, or, if both, why.
The disparity was quantified using both rate difference (the authors did not specify an exact percentage point difference between the immigrant vs. non-immigrant groups so I'm not sure if that technically still counts, but they did give a p-value on whether there was a significant difference) and multivariate logistic regression analyses (odds ratios). The former is an absolute measure and the latter is relative. For this research area, I would prefer both types of measures, because ideally women would be counseled on 100% of the prenatal topics outlined above, so it is useful to see both absolute percentages of prenatal topics counseled to patients as well as a relative measure to compare likelihood of their receiving counseling in each topic.