SECONDARY DATA ANALYSIS

Overview

Background Components Examples Challenges Opportunities

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 “primary analysis of existing data” or “archival data analysis” Distinguishes from merely re-testing the same

hypotheses

Data Sets: Examples

Inter-university Consortium for Political and Social Research (ICPSR) http://www.icpsr.umich.edu/icpsrweb/ICPSR/

access/subject.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 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

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)

Salzman study as of 9/24/15

Data Set

PI

Mentees ExternalCollaborators

Failed Aim 1

Article

ArticleManuscriptSubmitted

Manuscript

Manuscript

Manuscript

ManuscriptSubmitted

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FundedGrant

FundedGrant

FundedGrant

ManuscriptSubmitted

MastersThesis

ManuscriptSubmitted

Manuscript

Manuscript

Manuscript

FundedGrant

FundedGrant

FundedGrant

Also: 16 conference posters/presentations, 3 promotions, 3 students advancing on to higher degree programs, 4 students who were able to attend a national conference