Tenei ka waiho i te āpitihanga hangarau i runga i te anga putanga pea; hoki ētahi atu pārongo, kite Morgan and Winship (2014) ko Imbens and Rubin (2015) . Ka whakapuaki i te tāpiritanga te whakaaro e whai ake nei i roto i ngā o te putanga o ēnei:
Te tāpiritanga ka ngā ano he rite o ngā kaupapa i waenganui i-, i roto i-kaupapa, me whakaaro whakauru. kia hoki te tāpiritanga ngā mōhiohio e pā ana te whakamahi i ngā mōhiohio i mua maimoatanga-no te hoahoa tātari ranei.