"The Champ" may not show up on the critics' all-time top-ten lists, but for many scientists, the 1979 flick about a beat-up boxer and his boy is considered the classic tear-jerker — so classic that a clip from the movie serves as the scientific standard for inducing sadness. But how did "The Champ" win its crown? And is it still a contender?

The "saddest movie in the world" has been the focus of Internet buzz ever since last month's Smithsonian.com report, which noted that the film has popped up in a wide variety of studies of depression and grief. For example, "The Champ" played a role in determining that depressed people aren't really more likely to cry than non-depressed people, and that people are more likely to spend money when they're sad.

That's not to say that the experimental subjects were forced to watch the whole 121-minute movie. Psychologists just used just used a 171-second clip in which the boxer (Jon Voight) goes down for the count, turning on the tears from his son (played by 9-year-old Ricky Schroder, in a performance that won him a Golden Globe). The scene was one of more than 250 film clips selected by psychologists James Gross and Robert Levenson on the basis of recommendations from movie critics, video-store employees and film buffs.

During the late '80s and early '90s, the researchers refined their list and ended up showing 78 clips to 494 undergraduates. Gross and Levenson hoped that various movies would get strong thumbs-up for eliciting amusement, or fear, or sadness, or contentment — but they didn't always hit the mark. For example, their top fear-inducing movies, "The Shining" and "Silence of the Lambs," ended up sparking too many other emotions as well.

In contrast, "The Champ" performed like ... well, you know. The movie "produced levels of sadness that were much greater than those for any other emotion," they wrote in their seminal 1995 paper, "Emotion Elicitation Using Films."

Even though that research is now 16 years old, it's been cited more than 300 times in other scientific articles, and Schroder's cry-fest is still being used as a downer in the lab. (For what it's worth, the best film on Gross and Levenson's list for eliciting amusement is the fake-orgasm scene from "When Harry Met Sally.")

Knowing which movies are reliably amusing or depressing is important for psychology experiments, because movies provide a relatively painless way to elicit a variety of emotions — especially the negative ones. Showing someone a sad film clip won't leave lasting mental scars. When you compare it with some of the other methods that can spark feelings of fear, anxiety or anger, such as drugs or electric shocks, the choice is a no-brainer.

But isn't it time to rerun the experiment with a new set of movies? What seemed sad or funny in the '80s may seem sadly dated or unintentionally funny in 2011. And indeed, clips from other flicks such as "Steel Magnolias" and "John Q." have stood in for "The Champ" in some recent studies of sadness. If you have any suggestions for the saddest movie scene ever (or film clips that are the best for inducing fear, amusement or contentment), feel free to list them in your comments below.

Someday, some scientist just might decide to do a sequel to the sad-movie saga. Will a new top tear-jerker rise up for a new generation?

"I know that others have been working on this (as have we)," Levenson, director of the Institute of Personality and Social Research at the University of California at Berkeley, told me in an email, "but I believe the champ still is 'The Champ.'"

Update for 5:15 p.m. ET Aug. 7: Stanford psychologist Sylvia Kreibig, who has done extensive research on emotion-inducing films, got back to me with this email:

"We have worked with two film clips for inducing sadness in our own research (Kreibig, Wilhelm, Roth, & Gross, 2007, 2011; Kolodyazhniy, Kreibig, Roth, Gross, & Wilhelm, 2011), 'Steel Magnolias' and 'John Q.' On a scale from zero (not at all) to 10 (extremely), these films received an average rating of 6.14, with a standard deviation of 2.13. However, we did not compare these films to 'The Champ.' 'Steel Magnolias' has been used in a number of other experiments for studying sadness and has been found to be effective. A study by Goldin, Hutcherson, Ochsner, Glover, Gabrieli, & Gross (2005) tested the neural bases of sadness using 'The Champ' for inducing sadness, which might be of interest to you.

"Besides the Gross & Levenson 1995 paper, there have been at least three other large-scale research studies on validating film clips for emotion induction, including a target category of sadness:

• In 1999, Hagemann, Naumann, Maier, Becker, Lürken, & Bartussek found the clip from 'The Champ' to elicit the strongest ratings for sadness among a selection of three sadness-inducing film clips (M=6.64; SD=2.35, on a scale from 0 to 9) and to be highly specific for eliciting the target emotion (90 percent hit rate). These results are based on a German sample, demonstrating that this film clip is effective across national and cultural borders.
• Hewig, Hagemann, Seifert, Gollwitzer, Naumann, Bartussek (2005) again tested a set of three sadness-inducing film clips (among other emotion-inducing films) and again found 'The Champ' to be very effective in inducing sadness (M = 7.21, SD = 2.07 on a scale from 0 to 9), while not strongly eliciting other emotions (again in a German sample).
• In a more recent study by a Belgium research team using film clips in French, Schaefer, Nils, Sanchez, Philippot (2009) reported a clip from 'City of Angels' (mean of 2.32 on a scale from 1 to 7) to be the most effective, considering discreteness of elicited feelings and mean feeling self-report, but their selection did not include 'The Champ.'

"You see that different film sets and different scales for rating have been used in these studies. There are ways for mapping different scales onto one common scale in order to compare these values, but then the question still remains whether people would nowadays still rate 'The Champ' clip as the strongest sadness-inducing film clip. 'The Champ' seems to be fairly robust against changes in preferences of cinematographic style, as much has changed in the movie world since the film's shooting in 1979. And psychological distance/immersion might influence a film's effectiveness in inducing the targeted emotion, rather than amusement at watching the film clip or nostalgia for times past ... So emotion induction in the psychology laboratory remains to be a challenging issue!"

More about emotions and movies:

• Botox paralyzes your emotions, too, study shows
• Stop the waterworks, ladies: Crying chicks aren't sexy
• Tears don't make you feel any better
• Brain-damaged woman feels no fear
• Scientists study the thrill behind a chill
• Gallery: Five boxing films that pack a punch

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