9th of April, 2008
Primary Outcomes
- Number of
serious medication errors
(see PILL-CVD definitions) per patient during the first 30 days after hospital discharge.
- Number of
preventable/ameliorable serious adverse drug events (ADEs)
(see PILL-CVD definitions) per patient during the first 30 days after hospital discharge.
- Number of
potential serious ADEs
(see PILL-CVD definitions) per patient during the first 30 days after hospital discharge.
Effect Modification (Interaction) Variables
- Level of health literacy
- Investigation site
Possible Confounders
- Number of Prescribed Medications
- Age
- Social support
- Educational attainment
- hospital service
- insurance
- income
- Cognitive function
- Primary language ( don't you think that cognitive function would account for primary language differences)
- Gender (including this variable won't do any harm, but doesn't have to be included if there is no evidence in the previous literature that gender is important and you see no reason why it should)
- Race (if you think that race is associated with income)
Not Confounders
- Number of Medication Changes During Hospitalization (Changes in prescription can be caused by intervention therefore this variable should not be included as a confounder)
Secondary Outcomes
- Number of actual severe ADEs
- Disease-Specific Quality of Life / Disease Control
- Health Care Utilization
Confounders
Confounders listed under Primary outcomes.
ANALYSIS
Baseline Analysis
The following baseline variables are summarized for the control and intervention groups and compared using Wilcoxon's rank-sum (for continuous variables) and Chi-Square test (for categorical variables):
- Level of health literacy
- Cognitive function
- Educational attainment
- Primary language
- Gender
- Race
- Age
- Number of prescribed medications
Preliminary Statistical Summary
The following variables are summarized for the control and intervention groups and compared using Wilcoxon's rank-sum test:
- Number of serious
medication errors
per subject
- Number of
preventable/ameliorable ADEs
per subject
- Number of
potential ADEs
per subject
- Number of
preventable/ameliorable ADEs
by severity
Primary Analyses
In the analyses that follow, the effect of health literacy level on number of (or at least one)
preventable/ameliorable serious ADE
is tested by introducing an interaction term (intervention with literacy level).
- We use logistic regression to assess the association between the presence of
preventable/ameliorable serious ADE
and intervention. The model controls for gender the confounders listed under Primary Outcomes.
- Logistic regression is used to assess the association between the presence of
potential ADE
and intervention. The model controls for the confounders listed under Primary Outcomes.
- Poisson regression (or proportional odds ordinal logistic regression) is used to assess the association between the number of
preventable/ameliorable ADEs
and intervention. The model controls for the confounders listed under Primary Outcomes.
Secondary Analysis
The effects of the intervention on quality of life, disease control are assessed using proportional odds ordinal logistic regression, controlling for baseline and the confounders listed under Primary Outcomes. The effect of the intervention on health care utilization is assessed using Cox proportional hazard model, controlling for the confounders listed under Primary Outcomes.
To Do
- To think about few things for the studio: screening, enrollment, confounders (which ones to choose in advance, which ones to see according to the distribution), think about the choice of primary outcomes (to look at the composite outcome or analyze them separately), what to choose as a modification effect (interaction; it is obviously level of health literacy, but may be also investigation site; to check for that or assume it exists)