We noted no evidence that the effect of isoniazid preventive therapy was restricted to patients who were positive on tuberculin skin test or interferon gamma release assay ( adjusted HR for patients with negative tests @ -LSB- @-@ -RSB- and @ -LSB- @-@ -RSB- ; for positive tests @ -LSB- @-@ -RSB- and @ -LSB- @-@ -RSB- , respectively ) .