{smcl} {* *! ml_sens.sthlp — metaLong for Stata 14.1}{...} {vieweralsosee "metalong" "help metalong"}{...} {vieweralsosee "ml_meta" "help ml_meta"}{...} {hline} {title:ml_sens — Time-Varying Sensitivity Analysis via Longitudinal ITCV} {title:Syntax} {p 8 17 2} {cmd:ml_sens} {it:yi vi} [{it:if}] [{it:in}] {cmd:,} {cmdab:stu:dy(}{varname}{cmd:)} {cmdab:ti:me(}{varname}{cmd:)} {cmd:metafile(}{it:filename}{cmd:)} [{cmd:alpha(}{real}{cmd:)} {cmd:delta(}{real}{cmd:)} {cmd:saving(}{filename}{cmd:)} {cmd:replace}] {title:Description} {pstd} {cmd:ml_sens} computes the Impact Threshold for a Confounding Variable (ITCV) at each follow-up time point. Two versions: raw ITCV (to nullify the estimate) and significance-adjusted ITCV_adj (to render the estimate non-significant). A time point is "fragile" if ITCV_adj < delta. {title:Required options} {phang}{cmd:study(}{varname}{cmd:)}, {cmd:time(}{varname}{cmd:)} — As in {helpb ml_meta}. {phang}{cmd:metafile(}{filename}{cmd:)} — Path to dataset saved by {helpb ml_meta}. {title:Options} {phang}{cmd:alpha(}{real}{cmd:)} — Significance level. Default 0.05. {phang}{cmd:delta(}{real}{cmd:)} — Fragility threshold. Time points with ITCV_adj < delta are flagged as fragile. Default 0.15. {phang}{cmd:saving(}{filename}{cmd:)} / {cmd:replace} — Save results. {title:Returned values} {phang}{cmd:r(sens)} — Matrix: {it:time theta se df sy r_effect itcv itcv_alpha fragile}. {phang}{cmd:r(itcv_min)}, {cmd:r(itcv_mean)}, {cmd:r(frag_prop)}. {title:Formulas} {pstd} sy2 = sum(wi*(yi - theta)^2) / sum(wi) [weighted variance of effects] {pstd} r = theta / sqrt(theta^2 + sy2) [correlation-scale effect] {pstd} ITCV = sqrt(|r|) {pstd} theta* = |theta| - crit*se; if theta* > 0: ITCV_adj = sqrt(|r*|), else 0. {title:Reference} {phang}Frank, K.A. (2000). {it:Sociological Methods & Research}, 29(2), 147-194. {hline}