Comparison of the OH 119 μm and CO(2–1) line profile. The CO(2–1) spectrum is extracted from a nuclear region corresponding to the ALMA beam size and is convolved to the resolution of the OH spectrum (FWHM ∼ 270 km s⁻¹). We identified four different cases: (i) OH absorption reaching high velocity (|v|> 1000 km s⁻¹), but no CO blue-shifted emission (00188−0856); (ii) CO outflow, but no sign of OH outflow (22491−1808); (iii) outflow detected in both OH and CO, but OH outflow maximum velocity (v₉₈) larger than CO outflow maximum velocity (20100−4156); (iv) OH outflow maximum velocity (v₉₈) smaller than CO outflow maximum velocity (15327+2340).