Facts

The appellant ([A.] , born 2000, represented by Procap Schweiz) has suffered from Trisomy 21 since birth. The IV-Stelle of the Canton of Zurich granted her a care contribution for mild helplessness from August 2002 and recognised a contribution for moderate helplessness from 1 March 2003 (decision of 26 June 2003). In the course of the 4th IV revision, this was converted on 21 July 2004 into a helplessness allowance, which was subsequently confirmed several times upon revision.

In July 2018 the IV-Stelle initiated a further revision procedure and arranged an on-site assessment (report of 31 August 2018; supplementary statement of 31 December 2018). By decision of 29 January 2019 it reduced the helplessness allowance from 1 July 2018 to one for mild helplessness.

The Social Insurance Court of the Canton of Zurich partially upheld the appeal by judgment of 29 April 2020. It confirmed moderate helplessness until the end of March 2019 and mild helplessness from April 2019. The court costs were imposed in full on the appellant; no party compensation was awarded.

Before the Federal Supreme Court, the appellant requests the annulment of the lower court's judgment and the continued award of a helplessness allowance of intermediate degree, alternatively a reallocation of the costs and compensation consequences. The IV-Stelle requests dismissal; the Federal Social Insurance Office waived a response.

The issue is whether the cantonal court violated federal law by confirming the reduction from an allowance of intermediate degree to one of mild degree, in particular regarding the existence of a revision ground, the assessment of the daily life activities (eating, dressing/undressing, personal hygiene) and life-skills accompaniment.

Considerations

The Federal Supreme Court examines violations of federal law (Art. 95 lit. a FSCA) and is bound by the lower court's findings of fact unless they are manifestly incorrect or based on a violation of law (Art. 97 para. 1, Art. 105 paras. 1 and 2 FSCA). The correct interpretation of the concept of helplessness is a question of law, whereas findings on limitations in daily life activities based on a sufficient assessment report are questions of fact.

The Federal Supreme Court confirms the lower court's revision ground. In the area of 'eating', in 2016 constant motivation for food and fluid intake was still necessary, whereas in 2018 only occasional prompts were required; she can also handle cutlery independently. A disturbed hunger and satiety sensation in Trisomy 21 does not exclude an improvement in the individual case. The entitlement to a helplessness allowance can thus be fully reviewed (BGE 141 V 9 E. 2.3).

For assistance with the six daily life activities, a distinction must be made between direct and indirect third-party assistance; indirect third-party assistance exists where the third person must prompt an activity that the person does not perform without prompting due to their psychological or mental condition (BGE 133 V 450 E. 7.2). Direct or indirect assistance required for several daily life activities is only taken into account once, applying a functional and holistic approach.

Life-skills accompaniment (Art. 42 para. 3 InvIA, Art. 38 InvIO) is an independent institution and comprises neither third-party assistance with daily life activities nor permanent care or personal supervision. Decisive is whether the person, left alone, would require substantial accompaniment and advice, irrespective of living arrangement, cost question and origin of the help. The specification through margin nos. 8050-8052 KSIH is objectively justified and compliant with the statute.

In the area of 'dressing/undressing', the appellant is functionally independent but needs support with weather-appropriate clothing and…