Development of the Mini‐Assisting Hand Assessment: evidence for content and internal scale validity

Abstract

AIM To describe the development of the Mini-Assisting Hand Assessment (Mini-AHA) for children with signs of unilateral cerebral palsy (CP) aged 8 to 18 months, and evaluate aspects of content and internal scale validity.METHOD The ability of the video-recorded Mini-AHA play session to provoke bimanual performance in children with unilateral CP and typical development was evaluated. Original AHA test items were examined for their suitability for younger children and possible new items were generated. Data from 108 assessments of children with unilateral CP (86 children, 53 males, 33 females; mean age 13mo, SD 3mo, range 8-18mo) were entered into a Rasch measurement model analysis to evaluate internal scale validity. A Spearman's correlation analysis explored the relationship between age and ability measures for children with unilateral CP. The frequency of maximum scores in 40 children with typical development (22 males, 18 females; mean age 12mo, SD 3mo) was examined. RESULTSThe Mini-AHA play session provoked bimanual responses in typically developing children 99% of the time. Person and item fit criteria established 20 items for the scale. The resultant unidimensional scale also demonstrated excellent discriminative features through high separation reliability. The item calibration values covered the range of person ability measures well. Age was not related to the ability measures for children with unilateral CP (r s =0.178). All children with typical development achieved maximum scores.INTERPRETATION Accumulated evidence shows that the Mini-AHA validly measures use of the affected hand during bimanual performance for children with unilateral CP aged 8 to 18 months. The Mini-AHA has the potential to be a useful assessment to evaluate functional hand use and the effects of intervention in an age group when potential for change is high.Children with unilateral cerebral palsy (CP) have one wellfunctioning side of the body and one side that is affected by a motor and sensory impairment.1,2 The unilateral impairment is often first observed as a preference for using one hand, while the other hand is used less effectively or sometimes not at all. The impact of having one less efficient hand on the development of bimanual skills is not well understood in children less than 18 months old as currently there is no way of measuring hand role differentiation and bimanual performance in this age group. 3For children older than 18 months, the Assisting Hand Assessment (AHA) is an evaluative, criterion-referenced assessment that measures how well the affected hand of children with a unilateral disability is spontaneously used as an assisting hand during bimanual task performance. To provoke bimanual actions, a standardized set of toys that require the use of both hands are provided by the examiner during a semi-structured play session. The play session is video-recorded so that 22 object-related actions of the affected hand can be scored. [4][5][6][7] Currently this test is suitable for children aged 18 months to 12 years. If...

Early reach to grasp development of infants with asymmetric brain injury on the Grasp and Reach Assessment of Brisbane (GRAB)

“…The mini-AHA is currently the only valid measure reported for infants confirmed with congenital hemiplegia, aged eight to 18 months, to examine the use of their impaired UL during bimanual tasks.The mini-AHA is based on the Assisting Hand Assessment (AHA; for children with uCP and obstetric brachial plexus palsy, aged 18 months to 12 years), and involves a video-recorded, semi-structured play session whereby toys (designed to elicit bimanual UL use) 11,12 The mini-AHA involves a video-recorded, semistructured play session whereby toys (designed to elicit bimanual UL use) are provided to infants 12 The mini-AHA comprises 20 test items which are scored on a four-point rating scale, and from which raw scores are converted into logit scores (ranging from 0 to 100). 12 Intra-and inter-rater reproducibility of the mini-AHA, however, are yet to be established.…”

“…12 Intra-and inter-rater reproducibility of the mini-AHA, however, are yet to be established. 12 Modified Constraint casting, 15 and accompanied by shaping (which is a behavioural training technique that involves operant conditioning of movements of the impaired UL and motor recovery is achieved in small, successive steps). 16,17 Chapter 1: Introduction, thesis plan and aims…”

“…12 The mini-AHA comprises 20 test items which are scored on a four-point rating scale, and from which raw scores are converted into logit scores (ranging from 0 to 100). 12 Intra-and inter-rater reproducibility of the mini-AHA, however, are yet to be established. 12 Earlier detection of asymmetries in emerging UL motor behaviours in infants with asymBI would enable timely referral to interventions.…”

“…12 Intra-and inter-rater reproducibility of the mini-AHA, however, are yet to be established. 12 Earlier detection of asymmetries in emerging UL motor behaviours in infants with asymBI would enable timely referral to interventions. 188 The Hand Assessment for Infants (HAI) is currently being developed for infants with asymBI, aged three to 12 months, to: (i) examine the quality of goaldirected unimanual and bimanual actions during play; and (ii) detect asymmetries between ULs.…”

“…To date, the miniAssisting Hand Assessment (mini-AHA) is the only validated measure to evaluate the use of the impaired upper limb (UL) during bimanual performance in infants with UCP aged eight to 18 months. 12 There is no validated and published measure at present which evaluates asymmetries between ULs during early reach to grasp development in infants with asymBI who are younger than eight months C.A. Early detection of asymmetries between ULs is needed to provide an indication of an emerging hemiparesis in infants at risk of UCP.…”