def METHOD_NAME(self):
    # TODO: Return only the allowed instruments for at least one contained
    # analysis
    bsc = getToolByName(self, 'senaite_catalog_setup')
    items = [('', '')] + [(o.UID, o.Title) for o in
                          bsc(portal_type='Instrument',
                              is_active=True)]
    o = self.context.getInstrument()
    if o and o.UID() not in [i[0] for i in items]:
        items.append((o.UID(), o.Title()))
    items.sort(lambda x, y: cmp(x[1].lower(), y[1].lower()))
    return DisplayList(list(items))