Isdate, Isnumeric, IsEmpty (but no Istime?)

basically I am creating a form that needs to check that the inputs need to be in the correct format. The details are entered in various edit boxes in the form by the user and transfered to a locked sheet.

The macro that runs the dialog sheet form then interogates this cells in this sheet to check that the input is ok... so using Isempty(cell) =true in an if statement lets me give the user an error message and sends him back to the form if he forgets to put something in.

This works also to make sure that the input is a number or a date where required however I cant seem to find a way to make sure the user inputs a time where required as no Istime command seems to exist. Here is an example of whet I mean:

 weightm = DialogSheets("Dialog1").EditBoxes("Edit Box 69").Text
    [patweight] = weightm
    pw = Sheets("GFR").Cells(7, 4)
    If IsNumeric(pw) = False Then
GoTo Label6
    ElseIf IsEmpty(pw) = True Then
GoTo label3
    End If

Thanks very much

You can use the IsDate statement for times.