It or the study lacks …
The author appears to …
X overlooks …
earlier studies of …
the existing literature on …
recent work on …
Y’s findings …
important or crucial data on …
X’s study might benefit from …
The study has, in my view, several shortcomings: firstly, …
X seems to be unaware of …
X ignores …
X claims that …
…, which X claims …
X presupposes or assumes that …
X’s assertion that …
It is curious that …
It is odd that X does not mention …
a puzzling statement
the rather confusing statement that …
… can hardly be viewed as …
We believe this to be an error.
Serious doubts have been raised about …
a fundamental problem
a further or unnecessary layer of complexity
X fails to mention that …
There is no reference to …
Surprisingly, no mention is made of …
we are not told whether …
The study fails to address the question …
X pays scant attention to …
to cut corners
the integrity of the data
anecdotal evidence
ad hoc explanation
dogmatic
sweeping generalizations
X’s argument, point etc. that …
is too broad in scope
is too selective
is not new
echoes of …
Reading X, one is reminded of …
… is merely reinventing the wheel