This web site gives the opinions of Dr. Greg Kane. Everything you read here is expressed only as my personal opinion.

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NHTSA contract scientist Dr. Jack Stuster's email threatening me (as I read it).
NHTSA scientist and SFST validation study author, Dr. Stuster, defends NHTSA validation theory and corrects my scientific analysis. I show why I respectfully decline the doctor's corrections.

I started reading scientific literature in medical school, in the '80s. I know scientific spats can get snarky, but I'd never heard of one researcher threatening another— over scientific opinions! Then I got the email I've pasted below (with my emphasis added).The email includes this:

"I cannot find one claim in your rant that is supported by the evidence or accepted statistical methods. Responses to your most egregious misrepresentations are listed below...

["corrections" of my (Greg's) scientific results]....

I will give you an opportunity to correct your website and remove the libelous statements. You really should accept my generosity in this regard. "


NHTSA contract scientist Dr. Stuster is confused. Scientists don't get to "give opportunities" to people who disagree with their science. Scientists don't get to use backhand threats—You really should accept my generosity— to coerce people who point out their scientific errors to "correct" their criticism. What scientists get to do is act like adults and accept that it's a big world, people disagree. What scientists get to do about criticism is refute it. Using science. If they can.

As a trained scientist Dr. Stuster knows this. He knows scientific opinions, even descriptions of how science was done badly, are not libelous or otherwise actionable. And yet he demands I correct my lies. And he says everything on the web site—"I cannot find one claim"— is a lie. But NHTSA contract scientist Dr. Stuster gives particulars about only three of my results. For the great majority of the scientific analysis presented here, he won't say what my lies are. He'll only say I must remove them. Or else. The only way to avoid a lawsuit (is that the threat?) is to remove this web site completely.

I replied to the NHTSA's contract scientist Dr. Stuster. I told him I read his email as a threat. I asked him to make his threat specific—something more than not one claim. Exactly what claims does the NHTSA's scientist demand I change? As of this writing NHTSA scientist Dr. Stuster has not made his demands specific. He has not withdrawn his threat.

These sweeping demands by the NHTSA's scientist are, in my opinion, a naked attempt to suppress otherwise irrefutable scientific criticism of important NHTSA policies.

The purpose of FieldSobrietyTest.info is to let people know my scientific opinion of the science behind the NHTSA's SFST validation theory. I will continue to do that.

Top

And why does the author copy the email to an NHTSA Division Chief? Does

Garrett Morford, Division Chief
Enforcement and Justice Services Division
National Highway Traffic Safety Administration
1200 New Jersey Avenue, Room W44-312 (NTI-122)
Washington, DC 20590

approve of his scientists intimidating Americans who criticize the NHTSA? I don't know. He was sent Dr. Stuster's email back in early July 2008, so he apparently knows about NHTSA contract scientist Dr. Stuster's ongoing threat. But he hasn't prevailed on NHTSA contract scientist Dr. Stuster to withdraw the threat. I've written Mr. Morford to find out why. I'll keep you posted.

From: Jack Stuster [jstuster [at] anacapasciences.com]
Sent: Tuesday, July 08, 2008 5:33 PM
To: 'G Kane'
Cc: Garrett.Morford [at] dot.gov

Subject: Your Website

Greg:

I just found your website (by accident, actually) and am appalled by your misrepresentation of the 1998 field study and its results (http://fieldsobrietytest.info/index.html). I cannot find one claim in your rant that is supported by the evidence or accepted statistical methods. Responses to your most egregious misrepresentations are listed below.

Simply by adjusting the balance of impaired and sober drivers in the study group, NHTSA contractors can dial in the accuracy their research "discovers." And Simply by manipulating the group of drivers you choose to “study,” you can set up your validation study beforehand so it is certain to “discover” whatever arrest accuracy you’ve been paid to validate.

Neither NHTSA nor I selected the drivers who were stopped. Drivers were stopped during the study period who officers observed exhibiting a driving error or violation, which is the only legal procedure that could be followed to assess the SFSTs under field conditions. Only one case was excluded from analysis and that was because the driver refused all chemical tests. There was no a priori selection of subjects and NO manipulation of data, except by you in your examples.

If you are being paid to discover an accuracy of 91%, set up a study group 83% of whose drivers are impaired.

I was NOT paid to discover that the SFSTs were accurate and I am offended by your libelous statements. I was paid to conduct a field study and to analyze and present the results. I have reported unwelcome results on many occasions when the data do not support a hypothesis and was under no obligation to perform my work differently during this study. I am angered by your unfounded accusations concerning my integrity.

According to the NHTSA, officers using standardized FSTs still arrest 29% of the innocent drivers they assess.

Only three drivers were arrested during the study who had BACs below 0.08: one was under the influence of drugs (BAC=0.0), one was too impaired to drive at 0.07, and one was 18 years old with a BAC of 0.07 (in a zero-tolerance state). Not a single “innocent driver” was arrested. How can you claim otherwise?

I will give you an opportunity to correct your website and remove the libelous statements. You really should accept my generosity in this regard.

Sincerely,

Jack

Jack Stuster, PhD, CPE
Anacapa Sciences, Inc.
301 E. Carrillo Street Santa Barbara, CA 93101
Telephone: 805-966-6157 ext. 21
Fax: 805-966-7713
www.anacapasciences.com

Top

Let me be clear here, as I am clear in the rest of this web site:

 
 

The NHTSA claims officers using the One Leg Stand test are extremely accurate at predicting drivers' Blood Alcohol Concentration. Look at the graph. Do you really believe that by relying on a drivers' OLS score, you can be "extremely accurate" at identifying his BAC? The R^2 value is 20%, for goodness sake. That means 80% of the variation in people's One Leg Stand performance is caused by things other than their alcohol level.

After I included this graph here at FieldSobrietyTest.info, the NHTSA's contract scientist and San Diego study author Dr. Jack Stuster wrote me that he "cannot find one claim in your rant that is supported by the evidence," and threatening me, as I read his email, to correct my lies—or else.

Is this graph a lie? See for yourself. Download the Excel file with the San Diego data and have Excel make a scatter plot chart of OLS score vs Driver BAC. This should take about a minute. See what I mean? This graph is not in the NHTSA report—why?— but it is in the data.

NHTSA contract scientist Dr. Stuster's sweeping demands are, in my opinion, a naked attempt to suppress otherwise irrefutable scientific criticism of important NHTSA policies.

This web site is not about Jack Stuster PhD, CPE

This web site is about the mathematics of the NHTSA's SFST validation theory. In my opinion that theory, and the agency's supporting validation studies, are scientifically flawed. I formed my opinions after careful and precise mathematical analysis of the data from the San Diego SFST validation study. This web site explains the results of those calculations. This web site is about science. This web site is not about Dr. Jack Stuster.

Of course I can't describe the science in this NHTSA study without telling you which study I'm talking about. And I can't cite the study without naming the study's authors, one of whom was Jack Stuster, PhD, CPE. But I do not know, I do not care, I do not have an opinion about what Dr. Jack Stuster knew, or didn't know, or did intend or didn't intend at any time ever in his scientific research career. Nothing here is a claim or statement about those things.This web site is not about Jack Stuster, PhD, CPE. This web site is about the flawed science in the NHTSA's SFST validation theory—and in every courtroom where SFSTs are allowed as evidence.

The purpose of FieldSobrietyTest.info is to let people know my scientific opinion of the science behind the NHTSA's SFST validation theory. I will continue to do that.

Top
No need for threats

NHTSA scientist Dr. Stuster doesn't need to threaten me. My interest is the truth. I am happy to give the world my scientific opinions and let the market place of ideas sort out who is correct. I've posted the study data, so other folks can repeat the my calculations. I will be honestly and sincerely grateful for any factual / mathematical errors Dr. Stuster points out to me. Correcting mistakes will only make FieldSobreityTest.info better.

If Dr. Stuster and I disagree on scientific points I am happy to post on FieldSobreityTest.info any specific rebuttal/ correction he has, or to link to the best ass-kicking reply he cares to post on his own site.

I have asked Dr. Stuster to make his threat more specific. What exactly does he imagine needs correcting? For example, since Dr. Stuster "cannot find one claim in your rant that is supported by ... accepted statistical methods," I've asked him to name the accepted statistical methods he has in mind, and the basis on which he believes them to be generally accepted.

So far Dr. Stuster hasn't named those methods or cited those sources.

Since Dr Stuster has already compared the results of my many specific and precisely stated mathematical claims with what he believes the evidence actually shows, I asked him please to take just a few seconds more to copy and paste the results of his own parallel calculations into an email to me.

So far Dr. Stuster hasn't sent those calculations.

In fact, other than the three original complaints in his ominous email, Dr. Stuster still hasn't given any specifics. When he does I'll be happy to fix my errors. Fixing errors will only make FieldSobreityTest.info better.

Dr. Stuster defends NHTSA validation theory
From his email, here are SFST validation scientist Dr. Stuster's corrections of my analysis of SFST validation theory's two great flaws, "using SFSTs" and accuracy. I respectfully decline his corrections.

Top1 "Using SFSTs"

Dr Stuster writes:

[Quoting Greg's lies at FieldSobrietyTest.info]
According to the NHTSA, officers using standardized FSTs still arrest 29% of the innocent drivers they assess

[Dr. Stuster responds]
Only three drivers were arrested during the study who had BACs below 0.08: one was under the influence of drugs (BAC=0.0), one was too impaired to drive at 0.07, and one was 18 years old with a BAC of 0.07 (in a zero-tolerance state). Not a single “innocent driver” was arrested. How can you claim otherwise?


Greg replies
This is going to come down to the failure of SFST validation theory to settle on a single meaning of "using." First, the facts. Here are two versions of the contingency table tallying the findings of the San Diego study regarding officer BAC estimates compared with actual BAC levels.

NHTSA's official report

Greg's version
Same data, more calculations

The NHTSA's official report gives prevalence dependent accuracies only. These accuracies do not apply to drivers not in this study group.

The NHTSA's official report fails to disclose the scientifically standard, prevalence independent, statistics specificity and sensitivity. Thus the study avoids letting on that the accuracy of officer BAC estimates on innocent people is only 71%

Greg's version of this same data adds two standard scientific calculations:
impaired driver accuracy (sensitivity) = 98%
innocent driver accuracy (specificity) = 71%.

These accuracies are not prevalence-dependant, so they apply to drivers not in the study. Which is why established scientific journals require them...


The point Dr Stuster disputes is that if officer arrests are guided by officer BAC estimates (which we are told to believe are arrived at by "using SFSTs") then officers will arrest 29% of the innocent people they assess. To the extent officers do not arrest drivers who fail the SFST, officers are not using the SFST.

But, says Dr. Stuster, officers didn't arrest all those innocent people. Innocent driver arrest wise, officers "using SFSTs" were perfect.

What Dr. Stuster fails to say is officers weren't using just SFSTs. They were also using portable breath testing machines! Officers stopped drivers, did SFSTs, estimated BACs, then did a portable breath test for actual alcohol level.

Dr. Stuster asks us to believe SFSTs are accurate because officers "using SFSTs" estimated drivers to have high alcohol levels, then did a breathalyzer that proved otherwise, after which the innocent drivers were released. What crime officers might arrest just-proven-innocent people for, Dr. Stuster doesn't say.

Good. We've clarified the facts and identified the thing Dr. Stuster and I disagree about. Dr. Stuster's meaning of "using SFSTs" includes officers doing SFSTs, but basing their decisions on a breathayzer. I think what Dr. Stuster has in mind is better said, "doing SFSTs, but using a breathalyzer (or other non-SFST facts)" In my opinion, "using SFSTs" should mean "were guided by SFST results" -- that officer results and SFST results matched.

Either definition works, as long as you're consistent. The trouble with NHTSA SFST validation theory is, it fails to be consistent about this definition. More on this in a minute.

Now we know Greg's original point underestimated the SFST failure rate
The point Dr. Stuster imagines himself correcting was written before I had access to the San Diego validation study's data. Now that data is available, the point can be strengthened. If officers "using SFSTs" rely on those SFSTs to make their arrest decisions, they will wrongly arrest not 29% but 71% of the innocent people they assess.

Original claim
based on data in the SFST validation study report
revealing officer BAC estimates but not SFST results

Updated claim
based on raw SFST study data using standardized SFST interpretation criteria for BAC 0.08%

83 innocent people were assessed by officers
Officers estimated 24 of those 83 innocent people had high BACs—29%

83 innocent people took the SFST
The SFST indicated that 59 of those 83 innocent people had high BACs —71%


 

Updated claim
based on raw study data
using standardized SFST interpretation criteria for BAC 0.04%

And if officers target a lower BAC with the more stringent standardized SFST interpretation criteria imagined to identify BACs of 0.04%, then officers will wrongly arrest 93% of the innocent drivers they assess.

Here are the facts >>

 

29 innocent people took the SFST
The SFST indicated that 27 of those 29 innocent people had high BACs—93%


To the extent officers do not arrest people the SFST instructs them to arrest, officers are not "using SFSTs." This is more than a pedantic quibble, because...

Imprecision about what "using SFSTs" means is a deep and fundamental flaw in SFST validation theory. Lets talk about that some more...

SFST validation theory defines "using SFSTs" two different ways.

SFST validation theory
in court

&   Greg

In court study officers "using SFSTs" is taken to mean "were guided by SFST results," as if study officers' decisions had matched SFST results. If test results and officer results had matched, SFST accuracy and officer accuracy would also match.

This version of "using" is critical to SFST validation theory. If true, it would mean that in any DUI prosecution having the SFST result would allow the prosecution to reproduce the high (albeit misleading) accuracy of officers in the validation study. But it is not true.

SFST validation theory
in validation studies

&   Dr. Stuster

In validation studies' official reports, "using SFSTs" means something else. Now it means nothing more than "doing SFSTs." Including, "Doing SFSTs, but ignoring the results." Officers did SFSTs, but they were free to accept or reject the results. Very often what officers did was reject them.

How do validation studies track SFST rejections? They don't. Any officer who did an SFST was counted as using the SFST. I am not making this up. Every time officers estimated BAC in accordance with standardized SFST interpretation criteria, they were reported as "using SFSTs." And every time officers violated clear and explicit SFST interpretation criteria, they were still reported as "using SFSTs"!

In making their BAC estimates officers rejected false positive SFST results 59% of the time—and every one of those SFST rejections was reported as an officer "using SFSTs."

And, as Dr. Stuster points out, in making their arrest decisions officers with breathalyzer results in hand rejected false positive SFST results 100% of the timeand Dr. Stuster's analysis reports every one of those rejections as an officer "using SFSTs"!

With Dr. Stuster's method—which is the NHTSA's SFST validation theory's method — SFST validation comes down to Heads I win, tails you lose.



TopHere's how Greg replied to Dr. Stuster:

Dr. Stuster, let me begin by explaining my rational. Our scientific disagreement on this point centers on what is, in my opinion, another of your scientific errors in this study. You failed to define and quantify "using." In your study, officers could, and repeatedly did base their decisions on something other than your clear and explicit SFST interpretation criteria. As you write on page 20 of your report:

It is unknown why the officers did not follow the test interpretation guidelines in these two cases.... Similarly, in seven of the false positive cases listed previously in Table 6 officers apparently did not follow the test interpretation guidelines...

In your analysis of your data you used these results to tally the accuracy of officers "using" SFSTs. When officers' decisions were guided by the SFST, you counted them as "using" the SFST. When officer decisions clearly and repeatedly violated standardized SFST criteria, you still counted them as "using" the SFST.

You apparently chose not to investigate how often this happened. I did. In examining your data I discovered, as I have mentioned, that officers based their decision on something other than your standardized interpretation criteria fully 59% of the time—when the SFST error would have lead to a mistaken arrest, but only 2% of the time when the SFST error would have led to a mistaken release. The probability that this distribution of SFST rejections happened by chance is tiny. Dr. Stuster, your own study officers systematically ignored the standardized SFST interpretation criteria.

Further Dr. Stuster, it seems to me that in order to know which SFST results to ignore and which to accept, officers must have based their decisions on something other than the SFST in every case. In short, in my opinion, the science proves that officers in your study simply did SFSTs, but their decisions were not guided by the standardized SFST interpretation criteria.

This conclusion is confirmed by the officers' BAC estimates – to two decimal places. Nothing in the standardized interpretation criteria allows BAC estimates to this precision. And yet officers made predictions to this precision, and you used those predictions to "validate" the SFST. You did not "validate" the SFST results, you "validated" the officers BAC estimates. The officers' BAC estimates were not, and could not have been, derived from the drivers' SFST results and the standardized SFST interpretation criteria.

In my opinion, the science is clear. Officers in your study did SFSTs, they did not use SFSTs. Their decisions were not controlled by the standardized SFST interpretation criteria.

Now to your analysis of this particular claim. First, as you write in your report, page 10:

All police officers participating in the study were equipped with NHTSA approved, portable breath testing devices to assess the BACs of all drivers who were administered the SFSTs, including those who were released without arrest.

Dr. Stuster, if it is your position that the SFST is valid because officers using breath testing devices released innocent drivers who failed the SFST, then we have identified a point at which our opinions disagree.

You ask, so let me explain the basis of my claim. Using your data I calculate the decision matrix for the SFST as

At BAC 0.08% 83 innocent drivers were administered the SFST. Using the standardized FST interpretation criteria printed on page 12 of your study, I calculate that 59 of those drivers failed the SFST and 24 passed.

Dr. Stuster, in reviewing my claims and comparing them with the evidence, what were the results of your calculations here? If my calculations are incorrect, please let me know.

As to my claim, our difference seems to come down to, "using." As far as I can tell in your study you do not quantify what you mean by "using. If you do have a specific mathematical definition in mind, please let me know. Absent a definition from you, I used the one that seems most reasonable and that, I think, reflects the mistaken general understanding of your study's results. I intend "using" to mean "relying on," or "having their decisions controlled by." In this I am confirmed by:

"IT IS NECESSARY TO EMPHASIZE THIS VALIDATION APPLIES ONLY WHEN ...THE STANDARDIZED CRITERIA ARE EMPLOYED TO INTERPRET THAT PERFORMANCE.

IF ANY ONE OF THE STANDARDIZED FIELD SOBRIETY TEST ELEMENTS IS CHANGED, THE VALIDITY IS COMPROMISED."
NHTSA DWI Detection and Standardized Field Sobriety Testing, Student Manual, 2004 Edition, page VIII-19

It seems to me any definition of "using" other than "having their decisions controlled by" would violate these published NHTSA guidelines and amount to not using the SFST. Your data indicates that if officer decisions are in fact controlled by the SFST, officers will in fact wrongly arrest 29% of the innocent people they assess. To the extent your study officers did not arrest these people, they were violating the standardized SFST interpretation criteria and not "using" the SFST, in particular not as prescribed in the NHTSA's DWI detection manual.

Further on this point, would you agree with me that to the extent study officers violated and ignored clear and explicit standardized SFST interpretation criteria, the study fails to validate the standardized SFST interpretation criteria, but in fact validates the officers' unstandardized gut instinct?

If this is not true, it seems you must be saying, "If officers' decisions were controlled by the SFST interpretation criteria, the SFST is valid. And if officers' decisions were controlled by something else, in direct contradiction to the SFST result, the SFST is still valid." In which case, SFST validation comes down to Heads I win, tails you lose.

Dr. Stuster, if this analysis is mistaken, please show me how. I am anxious to make FieldSobreityTest.info as accurate as possible.

Top2 Skewed sample, skewed accuracy

Dr Stuster writes:

[Quoting Greg's lies at FieldSobrietyTest.info]
Simply by adjusting the balance of impaired and sober drivers in the study group, NHTSA contractors can dial in the accuracy their research "discovers."
And Simply by manipulating the group of drivers you choose to “study,” you can set up your validation study beforehand so it is certain to “discover” whatever arrest accuracy you’ve been paid to validate.

[Dr. Stuster responds]
Neither NHTSA nor I selected the drivers who were stopped. Drivers were stopped during the study period who officers observed exhibiting a driving error or violation, which is the only legal procedure that could be followed to assess the SFSTs under field conditions. Only one case was excluded from analysis and that was because the driver refused all chemical tests. There was no a priori selection of subjects and NO manipulation of data, except by you in your examples.

Dr. Stuster imagines himself correcting my analysis of SFST validation theory's "accuracy" flaw. My analysis is two fold.

First, it is generally wrong—unhelpful, uninformative, irrelevant, misleading—to report diagnostic test accuracies with just the accuracy statistic. The accuracy statistic NHTSA validation theory imagines "validates" the SFST in fact applies only to the group of drivers in the validation study. In other groups the test will have other accuracies. Accuracies that swing from zero percent to one-hundred percent, depending entirely on the the mix of drivers in the test group.

Accuracy explains why the accuracy statistic works this way. The page gives an example showing exactly how it works, and cites and quotes the solution to this group-dependence problem used by, among thousands of others, the worlds largest medical journal—to be meaningful, studies must report accuracy using non-group-dependent statistics. This is as basic as basic science gets.

To this point Dr. Stuster has no defense. He offers no analysis, no equations, no text to support SFST validation theory's imagination that the accuracy statistic reported in SFST validation studies is the number that reflects the probability that a DUI defendant who failed an SFST did in fact have a high BAC. He does not because he cannot. It isn't true.

Second, I observe that NHTSA validation studies skew their sample populations, their study groups, in a way that inflates the accuracies they discover. They load up on drunks.

Dr. Stuster does not deny that SFST validation studies' study groups are skewed toward impairment. He does not deny that those skewed groups inflate the accuracy the studies "discover." Let us accept he cannot.

QED. At this point my analysis is complete. It is is generally wrong—unhelpful, uninformative, irrelevant, misleading—to interpret diagnostic test results with just the accuracy statistic. What's more, the high accuracies "discovered" by NHTSA validation studies are caused by, would not have happened but for, the skewed samples.

 

Dr. Stuster writes "There was no a priori selection of subjects"
Dr. Stuster is mistaken. Before the first officer set out on his first patrol, the San Diego SFST validation study's study design assured that the group of people who would be studied would be skewed toward drunks. The study design excluded drivers who drove well. The study design excluded people driving during the day (officers patrolled late at night). The study design excluded drivers who looked and smelled and acted sober. In fact the study design deliberately excluded everyone highly experienced DUI patrol officers thought was sober.

Using those inclusion criteria, and big city late at night patrol tactics, veteran DUI officers were able to come up with a study group that was 90% guilty, at 0.04% BAC, before they began doing SFSTs. And after they did their SFSTs? After doing SFSTs, they ended up with a group of drivers that was 91% guilty. The SFST itself is responsible for 1% of that 91% accuracy!

Dr. Stuster continues: "There was... NO manipulation of data, except by you in your examples."

I never said there was.

A personal note
Since Dr. Stuster seems to take my scientific criticisms of his scientific work personally enough to threaten me, here's a personal note. I came away from my first exchange with Dr. Stuster, the one where he quickly and kindly sent me the study's data, feeling he is an honest, earnest FST believer. Wrong, but honestly so. He was cheerful and friendly. Nice. I still believe that.

On account of which, I feel particularly bad about attacking the science in Dr. Stuster's scientific paper. I suspect my scientific criticisms of his scientific method are new and surprising to him. It is only natural that he takes them to be personally hurtful. I understand the impulse to lash out. Unfortunately I must balance my professional unkindness to him against the harm done by what I understand to be faulty sobriety tests.

 

TopHere's how Greg replied to Dr. Stuster:

First Dr. Stuster, this claim does not name you. It does not say that you or anyone else did anything. It merely states a scientific fact: it is possible to change the accuracy a test discovers by changing the group studied. To identify a scientific error, I must first describe what the error was.

Second, when you write "Neither NHTSA nor I selected the drivers who were stopped," you are refuting a point I do not make. I do not believe and have never written that you yourself selected individual test subjects, or that you were in any way dishonest or manipulative of the data.

Let me further explain my scientific opinion of your scientific methods.

Your error was not in personally selecting the drivers who were stopped, Your error was in having officers select only drivers who were stopped, and worse than that only drivers who showed signs of impairment. In my opinion the way the math works out, the non-random sampling you designed into your study directly inflated the "accuracy" you discovered, compared to the accuracy you would have discovered if you had chosen subjects at random from the population, or at random from drivers in general. This is not a claim that you had knowledge or intention to deceive. It is simply a statement of basic mathematics.

The standard formula for this is:

Where PPV is Positive Predictive Value – effectively the "accuracy" you report. As you will quickly see, the "accuracy" is a function of prevalence—the percentage of people in the sample group who have the condition tested for. Adjusting the prevalence adjusts the "accuracy" you discover. Again, this is not a claim you had knowledge or intention to deceive. It is simply a statement of basic mathematics.

My own calculations indicate this study design error explains all the NHTSA's FST validation successes. Studies designed with non-random samples leading to inflated high-BAC prevalences "discover" high accuracies. Studies with low high-BAC prevalences do not. When the inflated prevalences are removed, the high "accuracy" disappears. The amount of knowledge about impairment added by the SFST is so low as to be not relevant to decisions about guilt.

 

Top3 Intent to deceive

Dr Stuster writes:

[Quoting Greg's lies at FieldSobrietyTest.info]
If you are being paid to discover an accuracy of 91%, set up a study group 83% of whose drivers are impaired
.

[Dr. Stuster responds]
I was NOT paid to discover that the SFSTs were accurate and I am offended by your libelous statements. I was paid to conduct a field study and to analyze and present the results. I have reported unwelcome results on many occasions when the data do not support a hypothesis and was under no obligation to perform my work differently during this study. I am angered by your unfounded accusations concerning my integrity.

I don't know if Dr. Stuster is crooked or not. And I don't care. I care about SFST tests. NHTSA SFST validation theory is not wrong because NHTSA scientists are corrupt. NHTSA SFST validation theory is wrong because it ignores basic science.


"Authors are expected to provide detailed information about all relevant financial interests and relationships or financial conflicts within the past 5 years and for the foreseeable future (eg, employment/affiliation, grants or funding, consultancies, honoraria, stock ownership or options, expert testimony, royalties, or patents filed, received, or pending), particularly those present at the time the research was conducted and through publication, as well as other financial interests (such as patent applications in preparation), that represent potential future financial gain."

Journal of the American Medical Association
Instructions For Authors, 2008
, pg 2;
also in JAMA, July 2, 2008-Vol 300, No. 1


Here's how Greg replied to Dr. Stuster:

Dr. Stuster, the statement flatly does not refer to you. It explicitly and clearly refers to a hypothetical person. It clearly does so in order demonstrate the connection between "accuracy" and studies done on non-random sample populations.

Is this mathematical statement incorrect? If so how? I am anxious to correct any mistake I have made.

That said, if you believe some part of this is unclear, let me know what and how. I will rewrite the section to fix any confusion. I want FieldSobreityTest.info to be as clear as possible.

 

 

 

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