On my system (OSX 10.11.1) with Mathematica 10.3 executing 
Needs["CUDALink`"]
and then 
CUDAInformation[]
Yields an output with unevaluated raw code:
1 /. If[Which[Developer`CheckProtectedMode[CUDAInformation], 
   Throw[$Failed], ! TrueQ[GPUTools`Internal`ValidSystemQ[]], 
   Throw[Message[CUDAInformation::invsys, $SystemID]; $Failed], 
   True && ! 
     TrueQ[Quiet[
       StringMatchQ[
        GPUTools`Internal`VideoCardName[], ___ ~~ "NVIDIA" ~~ ___, 
        IgnoreCase -> True]]] && 
    GPUTools`Internal`VideoCardInformation["Description"] =!= 
     "Description", 
   Throw[Message[CUDAInformation::invdevnm, 
     GPUTools`Internal`VideoCardName[]]; $Failed], 
   GPUTools`Internal`$NVIDIADriverLibraryPath === $Failed || ! 
     TrueQ[Quiet[
       DirectoryQ[
        DirectoryName[GPUTools`Internal`$NVIDIADriverLibraryPath]]]], 
   Throw[Message[CUDAInformation::invdriv]; $Failed], 
   TrueQ[Quiet[
     DirectoryQ[GPUTools`Internal`$NVIDIADriverLibraryPath]]], 
   Message[CUDAInformation::invdrivp, 
    DirectoryName[GPUTools`Internal`$NVIDIADriverLibraryPath]]; 
   Return[$Failed], ! 
    TrueQ[GPUTools`Internal`$NVIDIADriverLibraryValidQ], 
   If[GPUTools`Internal`$NVIDIADriverLibraryVersion === $Failed, 
    Message[CUDAInformation::invdrivver], 
    If[GPUTools`Utilities`LibraryGetDirectory[
        GPUTools`Internal`$NVIDIADriverLibraryVersion] =!= $Failed && 
      TrueQ[Quiet[
        DirectoryQ[
         GPUTools`Utilities`LibraryGetDirectory[
          GPUTools`Internal`$NVIDIADriverLibraryVersion]]]], 
     Message[CUDAInformation::invdrivverv, 
      GPUTools`Utilities`LibraryVersionInformationString[
       GPUTools`Internal`$NVIDIADriverLibraryVersion]], 
     Message[CUDAInformation::invdrivverd, 
      GPUTools`Utilities`LibraryGetDirectory[
       GPUTools`Internal`$NVIDIADriverLibraryVersion]]]]; 
   Throw[$Failed], GPUTools`Internal`LoadCUDALibraries[] === $Failed, 
   Throw[Message[CUDAInformation::syslibfld]; $Failed], True, True], 
  Throw[Message[CUDAInformation::nodev]; $Failed], Throw[$Failed]]
I will file a bug report....
Note that in my case 
CUDAQ[]
returns 
False
Presumably CUDAInformation[] should return something sensible (like $Failed) when CUDA is not installed.