Complex sentence: The SSS is most commonly used in a research setting but may also be used by a clinician to assess the level of intervention or effectiveness of a specific treatment in order to compare a clients progress.
Split into simpler sentences: The SSS is most commonly used in a research setting but may also be used by a clinician. In a clinical setting the scale would be used to assess the level of intervention or effectiveness of a specific treatment in order to compare a clients progress.