Job hunting? Hide your religion (with one exception)

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A new study found that indicating religious affiliation or atheism on a resume often harms employment prospects, unless that religion is Judaism—in which case it may help.

The study, published in the journal Social Currents and first reported by The Washington Post, found that job applicants in the American South who indicated a non-Jewish religion were 26 percent less likely to be contacted by employers. Jews, meanwhile, saw either no differential from the religion-hiding control group, or in some cases saw an increased interest.

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Researchers sent 3,200 job applications to 800 postings in Southern cities through an employment website. The only thing distinguishing the fake candidates was a mention of religious affiliation, with some referencing atheism, Catholicism, evangelical Christianity, Judaism, paganism, Islam, or an invented religion called "Wallonian." A control group did not mention any affiliation.

Muslim applicants fared the worst, with 38 percent fewer e-mails and 54 percent fewer calls than the control group. Evangelicals received about as many responses as the control group, while any other religious affiliation did worse.

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"Only Jews escaped totally unscathed," the researchers wrote. "Not only did Jewish applicants not face discrimination but they also actually may have received preferential treatment by some employers..." The study hypothesized that Jews may have received this treatment because they have "deep historical roots in the South" and have assimilated more successfully than other religions.

—By CNBC staff