A/HRC/20/24 Alternatives to detention should have a human rights-based approach, be established by law, be non-discriminatory and be subject to judicial review and independent monitoring and evaluation. In designing alternatives to detention, Governments should pay attention to the specific situation of particular groups of migrants, such as children, pregnant women and persons with disabilities, and use the least intrusive measure possible. 74. The Special Rapporteur encourages States to collect disaggregated data on the number of migrants in administrative detention, the number of migrants who are subject to different types of non-custodial measures and the compliance rate with these measures, in order to evaluate their effectiveness. 75. The Special Rapporteur encourages States to share information with him relating to their experiences in applying alternatives to detention, with a view to identifying best practices. 76. The Special Rapporteur would like to encourage States that have not yet done so, to consider ratifying the International Convention on the Protection of the Rights of All Migrant Workers and Members of Their Families. 77. The Special Rapporteur would like to encourage States that have not yet done so, to consider ratifying the Optional Protocol to the Convention against Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment, and establish a national preventive mechanism mandated to visit all places of deprivation of liberty within their jurisdiction, including places where migrants may be detained. 78. The Special Rapporteur would like to encourage civil society organizations to continue their efforts to document and study the violations and abuses that migrants suffer in the context of detention, continue monitoring good practices of alternatives to detention, develop and continue assistance programmes to migrants deprived of their liberty, including legal aid, translation services and social and psychological assistance and visit regularly migrant holding centres and penitentiaries where irregular migrants are held. 20