Bottom line, as with influenza, it's sometimes really hard to parse out what the ultimate cause of death is, given that both viruses seem to strengthen other respiratory infections to the point that they kill where they normally wouldn't. A consistent methodology would definitely be prudent, to ensure you're not comparing apples to oranges, but that methodology, if different, would need to be applied retroactively to influenza counts in prior years for comparisons (if one were interested in comparing this to the flu, which many seem to be).