David Ekserdjian, an art historian and curator, who specialises in the 16th-century Italian Renaissance, says the database has a number of absences and inconsistencies. For example, a copy of Caravaggio’s Madonna of Loreto, 1604-06, is registered in the diocese of Siena, Tuscany, and dated to between 1600 and 1649, whereas the original, in the church of Sant’Agostino, Rome, is absent. Similarly, Donatello’s wooden sculpture of St John the Baptist, 1438, in Venice’s Santa Maria Gloriosa dei Frari church, is nowhere to be found, but a wooden crucifix that was only recently attributed to Donatello, dated to between 1440 and 1445, is already registered in the diocese of Padua.
It has some way to go, but it's a start! The Database can be found here: http://www.chiesacattolica.it/beweb/UI/page.jsp?action=home