4. Discussion
respiratory disease, brain damage
RESPIRATORY DISEASE, CORTEX
This pilot randomised controlled trial showed no difference on the HAI scores for the affected hand and both hands between infants receiving EI-UL intervention and infants receiving EI-UL–MuSSAP training. The intervention with and without integrated MuSSAP training seems to be feasible, and significant improvements and large effect sizes were found, immediately after treatment and after 8 weeks follow-up. In addition, faster On group level, no additional beneficial effects of the integrated MuSSAP (attention) training were found. The intervention effects in both intervention groups were similar and in line with previous research exploring the effects of baby-CIMT [In our study, we observed a large variation in (increase in) manual ability between infants. This observed interindividual variability was larger than observed in the typically developing infants and in accordance with previous studies [Visual data-exploration suggested that infants with lack of goal-directed movements at the start of the intervention and with diminished attention for the contralesional upper limb might benefit from MuSSAP training. Risk for diminished attention and goal-directed movements may be related to the location and the severity of the brain damage. From adult populations it is suggested that impaired attention to the contralesional side commonly occurs following brain damage to the right posterior parietal cortex [By exploring the outcomes on the measures regarding gross motor development and quality of life, infants in the intervention groups generally showed lower scores and a slower developmental rate compared to typically developing infants, confirming a correct selection of high-risk infants in the intervention groups. Infants receiving EI-UL seem to have slightly higher scores on the quality of life measure compared to infants receiving EI-UL–MuSSAP training. The lower quality of life scores in the infants receiving EI-UL–MuSSAP intervention may be associated with a larger number of infants with lower physical well-being due to respiratory disease (Inclusion of the infants was based on outcomes of cerebral imaging studies and the clinical judgement of the paediatric neurologist. At the time of inclusion, the asymmetry index cut-off values of the HAI [A limitation of the current study is that the effects of the intervention and the (additional) effects of development while growing two (T1) and four (T2) months older cannot be distinguished. Due to ethical concerns that would raise by withholding early intervention programs to infants at high risk of developing uCP, we did not include a group of infants with unilateral brain lesion receiving no intervention. We observed a decline in manual ability in six infants with unilateral brain lesion during follow-up, while in typically developing infants only increases were observed, as expected. The decline in manual ability during follow-up suggests the presence of an intervention effect, although the size remains unknown. It may also suggest that 8 weeks of intervention were too short to give sustained improvement. Though, in most cases, manual ability at follow up was still higher than manual ability at baseline.Another limitation was the lack of a clinical measure for attention (for the contralesional upper limb) at the start of the study. Therefore, we developed a scoring guideline (VOAAH) for scoring the videos made by the parents of the training sessions at home. The quality of these videos, however, was sometimes poor and scoring of the videos was a time-demanding procedure. For clinical purposes, a technology-based method (for example using gaze detection) may be a more feasible and reliable approach. Furthermore, it must be noted that looking at the wristband is a proxy measure of attention for the contralesional upper limb. Adding brain-based measures (e.g., electro-encephalography) to future studies may be of added value. This is a noninvasive, affordable technique that can be applied in young infants and children with CP [Furthermore, blinded scoring of the outcome measures was not achieved. The occupational therapist who coached the families during the intervention also performed the measurements and scoring, since she was the only certified HAI assessor available in our clinic. By scoring a random selection of HAI assessments by a second certified HAI assessor from a different rehabilitation center in the Netherlands followed by a consensus meeting, reliability of the HAI scoring was enhanced as much as possible.