Abstract
Near infrared broad band photometry and CO indices for a significant number of Violent Star Formation Regions are presented. The existence of a narrow correlation between W(H ) and IR colour is confirmed. The interpretation of this relation as an age sequence implies a correlation between CO index and W(Hp) which is not found. It is argued however that this failure is most likely a consequence of using narrow band filters to determine CO indices in objects with strong emission-line spectra.
