I am examinating the parent-child interactions between parents & child (0 to 4 y) and assess 3 phases of communication (following the Hanen Center in Toronto): contact, interactions & the extend of stimulating communication skills in their child. Hereby we look at the skills of parents: sensitiveness & responsiveness, affection; let the child take the lead & follow the lead of the child; provide reinforced stimulation (exaggerated facial expressions, stressing target words, use gestures and movement to accompany verbal language, ect.). To measure the validity of our instrument, it would be very interesting to measure the concurrent validity with your instrument. Best regards, Mie