 During direct observation of the client, the SLP will observe various aspects of the individual's speech behaviors.In particular, the therapist might test for factors including the types of disfluencies present (using a test such as the Disfluency Type Index (DTI)), their frequency and duration (number of iterations, percentage of syllables stuttered (%SS)), and speaking rate (syllables per minute (SPM), words per minute (WPM)).They may also test for naturalness and fluency in speaking (naturalness rating scale (NAT), test of childhood stuttering (TOCS)) and physical concomitants during speech ("Riley’s Stuttering Severity Instrument Fourth Edition (SSI-4)").