diff --git a/src/main/java/picard/analysis/directed/HsMetrics.java b/src/main/java/picard/analysis/directed/HsMetrics.java
index 47ec8ad9fe..92e91a985b 100644
--- a/src/main/java/picard/analysis/directed/HsMetrics.java
+++ b/src/main/java/picard/analysis/directed/HsMetrics.java
@@ -38,8 +38,8 @@
*
Metrics that are intended for evaluating the performance of the wet-lab assay that generated the data.
* This group includes metrics like the number of bases mapping on/off/near baits, %selected, fold 80 base
* penalty, hs library size and the hs penalty metrics. These metrics are calculated prior to some of the
- * filters are applied (e.g. low mapping quality reads, low base quality bases and bases overlapping in the middle
- * of paired-end reads are all counted).
+ * filters are applied (e.g. duplicate reads, low mapping quality reads, low base quality bases and bases
+ * overlapping in the middle of paired-end reads are all counted).
*
* Metrics for assessing target coverage as a proxy for how well the data is likely to perform in downstream
* applications like variant calling. This group includes metrics like mean target coverage, the percentage of bases
@@ -82,10 +82,11 @@ public class HsMetrics extends PanelMetricsBase {
/** The mean coverage of all baits in the experiment. */
public double MEAN_BAIT_COVERAGE;
- /** The number of aligned, de-duped, on-bait bases out of the PF bases available. */
+ /** The fraction of aligned, on-bait bases out of the PF bases available.
+ * (NOTE: This uses duplicate reads for both numerator and denominator) */
public double PCT_USABLE_BASES_ON_BAIT;
- /** The number of aligned, de-duped, on-target bases out of all of the PF bases available. */
+ /** The fraction of aligned, de-duped, on-target bases out of all the PF bases available. */
public double PCT_USABLE_BASES_ON_TARGET;
/** The fold by which the baited region has been amplified above genomic background. */