The latest in a series of high-profile retractions of research papers has people asking: What’s wrong with peer review? Scientific and medical journals use the peer-review process to decide which studies are【C1】_____of publication. But a string of【C2】__or fabricated research has made it into print. The problems were【C3】__only when outside researchers scrutinized the work and【C4】__a job that many believe is the responsibility of the journals: They【C5】_____the data.

The【C6】_____of retractions has been rising for years. On Tuesday, a paper【C7】__the discovery of a room-temperature superconductor was retracted by the journal Nature【C8】__physicists flagged problems with the study and Nature【C9】__its own investigation. The journal’s decision to retract the paper【C10】__the criticism it had received almost【C11】_____upon publication. But it didn’t ease critics of the peer-review process.

Typically, reviewers are working scientists selected by journal editors to【C12】_____submissions and recommend whether they should appear【C13】__. Their reviews are almost always provided for free as a service to the scientific【C14】__. And to facilitate fair assessments, their【C15】_____are usually concealed. But journal editors acknowledge that errors or fraud can escape notice because reviewers don’t audit underlying data sets.

【C16】_____only a small fraction of the millions of studies published every year are retracted, when questionable research does make it into the pages of a prestigious journal, the consequences can be severe and【C17】_____.

One suggestion for fixing peer review that【C18】_____frequently is to pay reviewers. But journals are【C19】__to add additional costs. Another suggestion is to bring some of the data-checking in-house, while continuing to【C20】_____outside reviewers to assess the scientific design and arguments in new work.

【C15】