Whenever improved basic information is required for the compilation of the harmonised indices, or when the need for improved comparability of the harmonised indices is identified in the methods referred to in Article 4(4), the Commission (Eurostat) may launch pilot studies, to be carried out on a voluntary basis by Member States.
Aon uair a mbeidh faisnéis bhunúsach fheabhsaithe riachtanach chun innéacsanna comhchuibhithe a thiomsú, nó nuair is léir an gá atá le hinchomparáideacht fheabhsaithe na n-innéacsanna comhchuibhithe sna modhanna dá dtagraítear in Airteagal 4(4), féadfaidh an Coimisiún (Eurostat) treoirstaidéir a sheoladh a bheidh le déanamh ar bhonn deonach ag Ballstáit.