Table 3. Gastrointestinal-Related and Giardia-Specific Diagnostic Tests During 180-Day Study Window (N = 2995).
| Test | All Outpatients (N = 2995) | Age <18 y (n = 910) | Age 18–64 y (n = 2085) | PValue | |||
|---|---|---|---|---|---|---|---|
| Any GI-related testa | 1853 | (61.9) | 578 | (63.5) | 1275 | (61.2) | .22 |
| Any Giardia-specific testb | 1515 | (50.6) | 523 | (57.5) | 992 | (47.6) | <.001 |
| ≥3 Giardia-specific tests | 744 | (24.8) | 300 | (33.0) | 444 | (21.3) | <.001 |
| Any O&P microscopy testc | 1181 | (39.4) | 404 | (44.4) | 777 | (37.3) | <.001 |
| Any Giardia enzyme immunoassayd | 924 | (30.9) | 354 | (38.9) | 570 | (27.3) | <.001 |
| Any Giardia indirect fluorescent assay | 58 | (1.9) | 12 | (1.3) | 46 | (2.2) | .11 |
| Any Giardia direct fluorescent antibodye | 51 | (1.7) | 18 | (2) | 33 | (1.6) | .44 |
Data are presented as No. (%) unless otherwise indicated.
Abbreviations: GI, gastrointestinal; O&P, ova and parasites.
a
GI-related tests include Giardia-specific tests, and are defined in Supplementary Table 1.
b
Giardia-specific tests are defined and listed in Supplementary Table 1.
c
Includes tests with or without trichrome stain.
d
This category includes “rapid” diagnostic tests (eg, ImmunoCard STAT).
e
Gold standard for Giardia diagnostic testing.