Address code review feedback: optimize string operations and update NEWS

Co-authored-by: d-morrison <2474437+d-morrison@users.noreply.github.com>

Author: Copilot

NEWS.md

@@ -2,7 +2,7 @@
 
 ## New features
 
-* Added `compare_seroincidence()` function for statistical comparison of seroincidence rates (#XXX)
+* Added `compare_seroincidence()` function for statistical comparison of seroincidence rates
   - Performs two-sample z-tests to compare seroincidence estimates
   - Returns `htest` format when comparing two single estimates
   - Returns formatted table with all pairwise comparisons for stratified estimates

R/compare_seroincidence.R

@@ -154,6 +154,10 @@ compare_seroincidence.seroincidence.by <- function(x, y = NULL, coverage = 0.95,
   comparisons <- list()
   idx <- 1
 
+  # Pre-compute string patterns for column relocation
+  strata_patterns_1 <- paste0(strata_vars, ".1")
+  strata_patterns_2 <- paste0(strata_vars, ".2")
+
   for (i in 1:(n_strata - 1)) {
     for (j in (i + 1):n_strata) {
       # Extract data for this pair
@@ -199,8 +203,8 @@ compare_seroincidence.seroincidence.by <- function(x, y = NULL, coverage = 0.95,
       # Reorder columns to put stratum variables first
       comparison <- comparison |>
         dplyr::relocate(
-          tidyselect::starts_with(paste0(strata_vars, ".1")),
-          tidyselect::starts_with(paste0(strata_vars, ".2")),
+          tidyselect::starts_with(strata_patterns_1),
+          tidyselect::starts_with(strata_patterns_2),
           .before = "incidence.rate.1"
         )