NBI clearance

The National Bureau of Investigation (NBI) clearance tells if there have been criminal cases filed in the courts of the Philippines against the maid. Its scope is not limited to only a certain locality; it covers the entire Philippines.

Limitations

The NBI clearance cannot tell if there have been civil cases filed against the maid. 

Also, if the criminal case against the maid is still with the prosecutor or the police or the NBI investigators (or let's just say, still under investigation) the NBI clearance will reflect nothing. That means she's cleared. A criminal case goes thru many processes before it gets filed in court, and while the case is still at these stages it will not be reflected in the NBI clearance.

Police clearance

The police clearance says the same thing as the NBI clearance. That is, it tells if there have been criminal cases filed against the maid in the locality where it was issued. The scope of the police clearance is limited only to a certain locality. That is unlike the NBI clearance.

Limitations

The police clearance cannot tell if there have been criminal cases filed against the maid in other localities in the Philippines.

Like the NBI clearance, the police clearance cannot tell if there have been civil cases filed against the maid.

Barangay clearance

The barangay clearance tells if there have been cases filed against the maid in the barangay. The scope of the barangay clearance is limited only to a certain barangay; it does not cover other barangays in the Philippines. 

Limitations

The barangay clearance cannot tell if there have been cases filed against the maid in other barangays in the country.