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. 2009 Sep 22;10:87. doi: 10.1186/1745-6215-10-87

Table 3.

Variables, Measures and Methods of Analysis

Variable/Outcome Hypothesis Outcome Measure Methods of Analysis
1) Primary
Intervention improved outcome from baseline to 6 months

a) Adherence at 12 months
Percent adherence in previous 30 days >95% [binary] Chi-squared test

b) Suppression of HIV viral load at 12 months Viral load ≤400 copies/ml [binary] Chi-squared test

2) Secondary
Adherence percentage at 12 months
improvement occurred
Adherence % (>95%) [binary]
Chi-squared test

HIV viral load at 12 months improvement occurred Viral load (copies) T-test

Immune reconstitution (change in CD4 T cell count from baseline) improvement occurred
Cd4 T-cells/mm3 (continuous)
T-test

Time to virological failure
Improvement occurred
Virological failure after successful suppression Kaplan-Meier survival analysis

Weight gain [lbs] and BMI
improvement occurred
Change in weight (lbs) and BMI [continuous] T-test

Occurrence of opportunistic infections (OIs)
improvement occurred
Presence of AIDS defining opportunistic infection [binary] Chi-squared test

Time to reporting of adverse drug events (ADEs)
improvement occurred
Presence of drug-related adverse event [time to event] Kaplan-Meier survival analysis

Deaths (all cause)
improvement occurred
All-cause mortality [binary]
Chi-squared test and Kaplan-Meier survival analysis

SF-12 improvement occurred Quality pf life questionnaire [continuous] T-test

Satisfaction with care provided improvement occurred Questionnaire [continuous] T-test

Level of disclosure of HIV status improvement occurred Disclosed to a family member [binary] Chi-squared test

Impression of stigma improvement occurred Questionnaire [continuous] T-test

Family dyamics improvement occurred Questionnaire [continuous] T-test

Employment attendance improvement occurred Questionnaire [continuous] T-test

Household member school attendance improvement occurred Questionnaire [continuous] T-test

Cell phones lost/stolen improvement occurred Presence of cellphone [binary] Poisson regression

Stopped taking HAART improvement occurred Self-report [binary] Chi-squared test

Required active tracing for 12 month follow-up improvement occurred Field officers [binary] Chi-squared test

3) Subgroup Analyses:
Regression methods with appropriate interaction term
 Urban vs. rural Distance affects adherence
Female vs. male Sex affects adherence
  Phone ownership (owned vs. shared) Ownership affects adherence
Level of education Low education affects adherence

4) Sensitivity Analyses: improvement occurred All outcomes
 a) Per protocol analysis  a) Chi-squared/T-test test
 b) Adjusting for baseline covariates  b) Multivariable regression
 c) clustering among individuals within a clinic  c) GEE

IMPORTANT REMARKS:

• The GEE[11] is a technique that allows to specify the correlation structure between patients within a hospital and this approach produces unbiased estimates under the assumption that missing observations will be missing at random. An amended approach of weighted GEE will be employed if missingness is found not to be at random.[12]

• In all analyses results will be expressed as coefficient, standard errors, corresponding 95% and associated p-values.

• Goodness-of-fit will be assessed by examining the residuals for model assumptions and chi-squared test of goodness-of-fit.

Bonferroni method will be used to adjust the overall level of significance for multiple secondary outcomes.