Filter the top backups excludes the system DB and others

SELECT top (18) a.name, b.type, MAX(b.backup_finish_date) LastSuccessfulBackup,

CAST((GETDATE() - MAX(b.backup_finish_date)) AS NUMERIC(5, 2)) IntervalInDays

, c.physical_device_name,b.backup_finish_date

FROM master..sysdatabases a

LEFT OUTER JOIN msdb..backupset b

ON a.name = b.database_name

LEFT OUTER JOIN msdb..backupmediafamily c ON b.media_set_id = c.media_set_id

where  b.type = 'D' and a.name not in ('msdb','master','tempdb','model','DBA')

GROUP BY a.name, b.type,c.physical_device_name,b.backup_finish_date

ORDER BY b.backup_finish_date DESC