NFL Commissioner Roger Goodell, left, and NFLPA Executive Director Demaurice Smith talk before signing the NFL's new 10-year collective bargaining agreement at the Pro Football Hall of Fame in August . (Jason Miller/GETTY IMAGES)

Do you swallow something when you don’t know what’s in it? Not if you have an IQ above room temperature. So why should NFL players, or any other athletes for that matter, be expected to swallow the World Anti Doping Agency’s method for HGH drug testing without independent scientific verification that it’s reliable, or fair, or applicable to them?

What if a stranger told you to take a blood test, showed you a vial and a needle and said, “Here, trust me.” What if the stranger told you that the result could cost you your income or even your job? What if, when you balked, he called you a coward and tried to force you to take it? That’s what NFL players are facing in their standoff with WADA and its American arm, USADA, over testing for human growth hormone.

“To me it’s clear that WADA is more interested in bullying us into a test than in scientifically supporting and justifying their testing protocol,” NFL Players Association Executive Director DeMaurice Smith said.

The union has taken the brunt of public criticism for the delay in implementing an HGH test, but WADA is equally to blame for its lack of transparency and refusal to answer some basic questions the union is asking — questions that Congress and NFL Commissioner Roger Goodell also should be asking. Questions such as: Is there enough independently published medical science that validates the test? How was it devised, and its parameters established?

Outside experts consider these questions quite reasonable and are asking them too. Doping researcher Don Catlin, founder of the UCLA Olympic lab and the man who cracked the Bay Area Laboratory Co-Operative case, doesn’t want to take a side, but he wonders why there isn’t more material on the test in peer-reviewed journals and noted that all of the scientists who support the test are employed by WADA. While the test may be sound, WADA’s secrecy is a basic violation of good science, he said.

“That’s odd to me,” Catlin said. “I don’t understand it. Scientists with a good finding are usually crawling to get published in a peer-reviewed journal so the world can see it.”

The NFL players are right to hesitate until their queries are answered, according to doping expert Charles Yesalis, professor of health policy at Penn State, who writes textbooks on anabolic steroids. “I love sport, but I’m not going to sacrifice scientific method to play cops and robbers,” Yesalis said.

One of the primary things the NFLPA is asking for and hasn’t gotten is the population study WADA used to develop the test. WADA claims to detect HGH by measuring isoform ratios in human blood: If you show a ratio beyond what WADA scientists consider your natural limit, you are considered guilty of HGH use. But natural limits can vary significantly among people. If you’re an NFL player, you don’t necessarily want to be compared with a Romanian gymnast.

The NFLPA quotes Martin Bidlingmaier, co-founder of the HGH test, who has said that gender, age, body composition, injury history, type of sport, diet and the effects of chronic exercise could all be relevant, and the ratios should be based on “a suitable reference population.” Is WADA’s reference population suitable for 300-pound NFL players? Is it suitable for 6-foot-6 NBA players? Whom did WADA conduct its trials on? Downhill skiers? How big were they, where do they live, what were their diets, their living conditions, their habits? WADA has only provided the NFLPA with some summary info, and not the study itself.

These sorts of questions are quite reasonable, according to Catlin. “You do want to test your test in the population that you’re going to be applying it to,” he said. “When WADA says we’ve already done that, my comment is, okay, show me your data, what did you do, who did you study and what were your results? That’s what independent scientists do.”

Another example: WADA has claimed there is only a 1-in-10,000 chance of a false positive. But Catlin said: “I don’t know where they got that. If they have actual data on that I’d certainly like to see it.” Nor does Yesalis know how WADA arrived at the figure; it simply announced it without providing the basis. “That’s not how science is done,” Yesalis said. “You publish, make it public, and let other scientists try to replicate your results.”

These are not small issues. Under the NFL’s proposed HGH code, players would be prevented from challenging the science behind the test in the event of a positive result. Once players agree to testing, they will have little legal recourse. So they need to be sure the test and the appeals process are fair. “The only right result in all of this is confidence in the testing procedure,” Smith said.

Asked to respond to union concerns, USADA executive director Travis Tygart said via e-mail, “The population study and the science behind the test is not really the issue; it is simply something the NFLPA is using as an excuse to delay doing what they agreed to do with the NFL in their collective bargaining agreement.” He also said “the world’s top scientists have all agreed that the test is scientifically valid” and contended that a separate NFL population study “is not necessary” and that “there is nothing unique about American football players.”

None of that breeds confidence without the scientific data. Nor does the fact that NFL players’ due process seems to have been already abused, and they haven’t taken a test yet. Tygart characterizes the union as stalling to protect “dirty” players. Whatever the union’s motives, to judge players already guilty simply for asking questions is, for lack of a better word, un-American. Smith called Tygart’s charge “repulsive” and wonders why he should submit to such an authority, and every American sports league should ask the same question.

Catlin believes WADA and USADA are reluctant to furnish data about the test because they don’t want to help athletes legally challenge it. “It could be used by lawyers against them,” Catlin said. “Well, yes it could. But that’s the nature of drugs in sports and the nature of lawsuits. You have to be able to prove your case.”

One solution to this impasse is for the NFL to simply go around WADA and USADA and develop its own testing. The union, in consultation with the anti-doping lab Aegis Sciences, proposes to do a new population study that would “fill the scientific void that WADA was unwilling to fill,” Smith said.

It’s hard to see how such a thing could hurt. The NBA players are also in discussions to adopt an HGH test but want it to be subject to the validation by “a neutral committee of experts.” That can’t hurt either. Fairness doesn’t come with secrecy. It comes with transparency.