A dwindling number of American Jews will bother attending a Passover Seder this year—but some may postpone their own deaths to take part in one, at least according to controversial research from the 1980s. For a 1988 paper in the British medical journal The Lancet, University of California at San Diego sociologists David Phillips and Elliot King analyzed mortality patterns in the period surrounding Passover, and found that death rates for Jewish men decline right before the holiday, only to rise sharply after it ends.
Looking to find empirical evidence to test the theory that people can delay their deaths—see, for example, Thomas Jefferson and John Adams's passing on the 50th anniversary of Independence Day—Phillips and King decided to look at deaths surrounding Passover. The Jewish celebration of the exodus from Egypt, they reasoned, should be a particularly suitable holiday for this project, not only because of its emotional significance for observers, but for methodological reasons: The researchers could find people who celebrate Passover and people who don’t within the same geographic location. Moreover, seasonal factors are at least partially mitigated by the fact that Passover moves around the springtime calendar. In order to test their hypothesis, Phillips and King looked at death certificates in California from 1966 to 1984, guessing which ones belonged to Jews by matching last names with those listed in A Dictionary of Jewish Names and their History, and leaving out names like “Rose” and “Green,” which are common among both Jews and non-Jews. For control groups, they used death certificates with unambiguously Chinese or Japanese surnames.
Phillips and King discovered a significant variation in death rates around Passover. When they looked at the 24-week period surrounding the holiday, they observed the lowest rate of Jewish mortality in the week preceding the first night and the highest rate in the week after it. Among the 1,919 Jewish deaths they identified over the 17 two-week periods before and after the first night of Passover, they found there were a total of 8.1 percent more deaths during the week following Passover than the week before. The fluctuation was significantly greater for men than for women: In fact, women’s mortality rates didn’t change in any significant way throughout the holiday period. Phillips and King connect this to the fact that it is traditionally the oldest man attending the Seder who leads the retelling of Exodus. And women with Jewish last names, they hypothesize, might not have been born Jewish; they could have taken the names of Jewish husbands. Phillips and King also found that the “Passover effect” was much stronger when the first night fell on a weekend: They observed a 61.4 percent increase in men’s deaths following weekend Passovers, compared to a 13.7 percent rise following weekday Passovers. People may be more likely, they theorized, to participate in a large Seder involving most of the family if the holiday falls on a weekend. “Our findings, that some people’s deaths are postponed until they have reached a meaningful occasion, are consistent with two hypotheses,” Phillips and King conclude, “that the ‘will to live’ is associated with reduced mortality, and that communal social events can have a beneficial impact on the course of disease.”
The Passover study followed up on a smaller 1973 study Phillips conducted with SUNY Stony Brook professor Kenneth Feldman. Feldman and Phillips looked at historical mortality rates surrounding Yom Kippur in New York City and Budapest, using death records in New York between 1921 and 1969—when 28 percent of the city’s population was Jewish—and in Budapest from 1875 to 1915, when 22 percent of residents were Jewish. They didn’t distinguish Jews from non-Jews, but they found that overall mortality rates were generally lower in the month before Yom Kippur, the Jewish Day of Atonement, and higher after.
Phillips’s findings have been disputed, most vehemently by Gary Smith, a professor of economics at Pomona College in California. In 2004, Smith, along with co-author Peter Lee of Columbia University, re-examined Phillips and King’s claim that Jewish men are more likely to die just after Passover. Smith used a different dataset: records from a Jewish funeral home in San Francisco. He and Lee collected data on 5,111 services between 1987 and 1995, and looked at the periods surrounding not only Passover but three other significant Jewish holidays, too: Rosh Hashanah, Yom Kippur, and Chanukah. They found no significant links between holidays and mortality, and when they looked at men’s deaths around Passover, the pattern they found was the opposite of the one Phillips identified: They saw a slight increase in deaths in the weeks before Passover. Smith argues that the dataset from the funeral home is more reliable; Phillips merely guessed which names were likely to belong to Jews, but everyone in Smith’s sample identified strongly enough with Judaism to be given a Jewish funeral. Smith’s study also looks at many more potential correlations; he’s suspicious of Phillips’s selection of Passover as the sole focus of investigation.
In 1990, in an effort to prove the delayed-death theory wasn’t limited to Jews, Phillips teamed up with Daniel Smith, another University of California at San Diego researcher, to see if the same pattern could apply to Chinese people in California. Using a similar type of dataset—death certificates from 1960 through 1984—Phillips and Smith calculated mortality rates among Chinese and non-Chinese surrounding the Harvest Moon Festival, an annual holiday that, like Passover, brings together the family, centers on a festive meal with special foods, and moves around the calendar. Phillips and Smith compared death rates among Chinese men, women, children, and non-Chinese people, in the 24-week period around the Festival. As they predicted, they found a dip in deaths in the week before the festival, followed by a spike the week after, with an especially strong effect among older women. If the two weeks surrounding the Festival were consistent with the entire 24-week period they studied, they would expect to see about 50 or 51 elderly women pass away each week, but in the week just before the Festival, only about 33 passed away; in the week after, 70 deaths occurred. “Unlike Passover,” Phillips and Smith reasoned, “The Harvest Moon Festival places great emphasis on the symbolic importance of old women.” It is the oldest woman who is in charge of preparing the ritual meal and directing the labor of the younger women.
These results have been contested, too. When Gary Smith re-analyzed the data on the California death certificates—broadening the sample to include Vietnamese and Korean-Americans, who also celebrate the Harvest Moon Festival—he didn't find such a dramatic death-dip before the holiday. Phillips, says Smith, mis-counted the deaths that preceded the holiday. According to Smith, the main ceremonial event of the Festival occurs at midnight at the end of the first day, so women who die before midnight should not be counted as postponing death—as Phillips does. “For women 75 and older, the data are not statistically persuasive unless a death on the Harvest Moon Festival day is considered to have occurred after the festival,” Smith concludes.
Whether or not Phillips’s results hold up, Jewish leaders panicking over the drop in Seder attendance should take note: Even if it's tenuous, the argument that people put off death to go to one is pretty persuasive.