Secondary Data Analysis

Overview What is “secondary data analysis”? How do you do it? What are the advantages and disadvantages?

What is it? (Hint: You’re already doing it) Secondary data analysis Analyzes data from an existing data set Data you did not collect yourself (colleague, collaborator, professor) Data from a study focused on something else (primary analyses/papers already complete) Data collected for some other purpose (medical records, transcripts, etc.) Also called “archival data analysis”

Data Sets: Examples Inter-university Consortium for Political and Social Research (ICPSR) http://www.icpsr.umich.edu/icpsrweb/ICPSR/access/su bject.jsp Catalogue of many public data sources Midlife in the United States (MIDUS) http://www.midus.wisc.edu/ National longitudinal study of health and well-being

Components 1. Permission 2. Data dictionary 3. Data file Often requires a “data usage agreement” Rules about which analyses will be conducted, authorship, timeliness May require IRB approval 2. Data dictionary Protocol, measures, descriptive statistics Quality varies: Non-existent, paper files, Excel, PDF 3. Data file SPSS, Excel, SAS, or something else

Challenges Upfront investment: Varying quality of data dictionaries and collaborators Imperfect measures You might want a quality measure of extraversion, and all they have is a single item on optimism Politics: Some psychology departments quantify science in terms of studies-per-paper rather than papers-per-study  may be viewed as lesser science, or may require theses/dissertations to use “original” data collection

Opportunities Upfront investment = delayed gratification Efficient on many levels Implementation, publishing, funding Significance High-quality studies May begin by asking the PI, “What is the most important finding in the data set you’ve never had time to publish?” Can be symbiotic (mutually beneficial) Own posters/presentations/publications, PI is happy for added productivity (publications are good, helps with funders), good way of building a new collaboration

Salzman study as of Feb 2017 Funded Grant Failed Aim 1 Also: 13+ conference posters/presentations, 5+ promotions, 4 students advancing on to higher degree programs, 5+ students who were able to attend a national conference Funded Grant Failed Aim 1 Article in Special Issue Funded Grant PI Manuscript Funded Grant Manuscript Submitted Data Set Manuscript Manuscript Submitted Manuscript Submitted Mentees External Collaborators Manuscript Masters Thesis Manuscript Manuscript Manuscript Submitted Funded Grant Article Funded Grant Funded Grant Article Honors Thesis Article