Khabar al-wāḥid is categorised, with respect to acceptance and rejection, into al-ṣaḥīḥ, al-ḥasan, and al-ḍaʿīf.
When the routes of a ḥasan li-dhātihi narration multiply, the ḥadīth is upgraded to al-ṣaḥīḥ li-ghayrihi (the sound by virtue of something other than itself).
If a ḥadīth of slight weakness comes through multiple routes, it becomes al-ḥasan li-ghayrihi (the fair by virtue of something other than itself).
A solitary report transmitted by an upright narrator of complete retention, with a connected chain, free of any concealed defect or anomaly, is al-ṣaḥīḥ li-dhātihi (the sound in itself).
