How Content Analysis Can Measure Health and Safety in Occupational Licensing Requirements

Should a quantitative analysis of the language of textbooks be methodologically controversial?

In my recent paper "Regulating Glamour," I found that only about 25% of the required training for barbers and cosmetologists is related to health or safety. This is a notable claim; readers may want to know more about the method used to derive it. In this post, I discuss the methods used to produce these findings. The article's method rests on what is called content analysis—to oversimplify, my content analysis rested on counting and analyzing the words and sentences in textbooks used by barbers, cosmetologists, and manicurists.

Let me begin with an explanation of state-required curricula for appearance professionals. Just as high school degrees in many states require a certain number of hours of instruction under state law in English, math, history, and so forth, in many states a degree in cosmetology requires a certain number of hours of instruction in such fields as haircutting, shampooing, hair coloring, and chemically relaxing the hair.

Consider the following two instances of the way that health and safety instruction might be included in the fields of a cosmetology curriculum. When cosmetology students are taught how to give haircuts, they are typically taught how to do so safely (for instance, you must clean and disinfect your instruments, or else you may spread disease); when cosmetology students are taught how to chemically relax hair, they are typically taught how to do so safely (for instance, you must not apply certain kinds of chemical relaxers to the hair if it has previously been colored with metallic salts, or else you may cause dangerous chemical reactions and hair breakage).

The Article's calculations rely on a survey of each relevant chapter of three leading textbooks for appearance professionals that describe health and safety rules, practices, and concerns (the three textbooks I used occupy roughly three-quarters of the student market): it is probably uncontroversial to say that the health and safety rules and concerns that the textbooks describe for haircutting are sparse, brief, often intuitive, and easy to remember; however, this probably is not true for the health and safety concerns that the textbooks describe for chemical hair relaxers, which are relatively extensive and abstruse (and, in a few instances, a little alarming: in some circumstances, misuse will cause hair to issue smoke or even to melt). This highlights what perhaps is obvious: the curricula for different fields can be expected to contain different amounts or proportions of instruction that are relevant to health and safety.

How might one determine what portion of training in some particular field is related to health and safety? This Article's methodology includes a content analysis of the latest edition of these textbooks so as to derive a health and safety rating for each field. In each case, I measured the portion of the text that pertained to health and safety. (The assumption here is that the relevant text about some given field is a reasonably complete account of the formal and theoretical aspects that students need to learn about that subfield; perhaps a critic of this assumption might argue that there is no significant relationship between the textbooks' content and what prospective appearance professionals must learn, but that critic would likely find it difficult to explain why so many professional schools assign and require a textbook.)

This measurement typically resulted in a ratio: for instance, if a field was entirely described in a particular chapter or subchapter in one of the textbooks, a figure based on the length of the health- and safety-related concerns and instructions in that text was then divided by another figure based on the length of the field's entire text. So, for instance, given a chapter that pertained to a particular field, if one-fifth of that chapter pertained to health and safety issues, I gave it a health and safety rating of 20%.

Assuming that this is a reasonable methodology for providing an estimate of the health and safety portion of a personal appearance curriculum, it follows that the number of hours of health and safety training for any given jurisdiction and subfield can be calculated: one simply multiplies the health and safety rating by the number of hours that the jurisdiction devotes to training in that subfield to arrive at an estimate of training, as expressed in hours, in health and safety for that subfield. For instance (and to put it less formally), this method finds that health and safety concerns constitute just over 3% of the relevant textbook's haircutting chapter. The significance of this is that if a jurisdiction's cosmetology curriculum requires 100 hours of haircutting instruction, this Article's methodology implies that just over 3% of the haircutting instruction—or 3 hours—is devoted to health and safety training.

This quantitative approach permits the calculation of the estimated portion of health and safety training in the required set of personal appearance subfields for any given profession and jurisdiction: this calculation is performed by summing all the hourly health/safety requirements for that jurisdiction that are already derived, then dividing that sum by the total number of hours that the jurisdiction requires.

Although one could argue that a significant degree of health and safety training is not well-measured by content analysis, given that such training sometimes takes place while performing appearance services rather than by learning abstract propositions, that argument would have some eyebrow-raising implications for the training of appearance professionals. For instance, cosmetology educators would presumably affirm that all students at their schools receive sufficient training to perform any particular procedure safely before those students are ever asked to perform that same procedure on a human volunteer; such an affirmation would be in some tension with the theory that students must perform cosmetic services on people in order to learn about health and safety.

Given some anecdotal accounts of real-world student practice on volunteers, there is reason to believe that this method might systematically overstate the quantum of health and safety training that such practice entails. In particular, there is anecdotal evidence that some of the requirements that some cosmetology students must fulfill, with respect to providing cosmetology services to the public, are satisfied whether or not a member of the public ever appears at the workplace to receive those services. In some states, in the event that no member of the public enters the workplace to receive cosmetology services, the training/education requirement can apparently be satisfied if the cosmetology student performs no services and does nothing but show up at the workplace. The health and safety portion of these education/training hours would presumably be zero.

Here's another way to think about how accurate this method is (more formally, we could view the following as a validity cross-check). Consider a more granular examination of one health and safety rating—namely, the training in haircutting that cosmetologists must undergo. Like most disciplines and crafts, the practice of cosmetology requires the internalization of skill sets as well as propositional knowledge. Only a subset of the practical and theoretical knowledge that cosmetology requires bears on health and safety.

A summary of health- and safety-related concerns related to haircutting in the relevant 46 pages of the relevant textbook's chapter—students must learn proper cleaning, maintaining, and disposal techniques for their haircutting instruments; proper holding of instruments during use; proper posture; and proper cutting techniques to enhance safety. In the 24 jurisdictions that expressly require cosmetology curricula containing a portion that solely focuses on haircutting, that portion's average requirement is roughly 175 hours; the article's content analysis method suggests that the required health and safety training aspect of such instruction would be between 5 and 6 hours. I invite the reader to determine to estimate, based on nothing more than common-sense experience, how long it should take to teach the set of health and safety propositions and procedures for haircutting summarized above—and, in particular, whether it should take significantly more or less than 5 or 6 classroom hours to impart this summarized information.

I would be interested in hearing from readers, in the comments, whether they view the article's method for estimating the health and safety portion of appearance professional training as well-grounded—and, furthermore, whether they can think of a better method for this kind of measurement. And I will close by expressing my gratitude to Eugene Volokh both for letting me post a few thoughts here and for providing many hours of fascinating reading over the years through the Conspiracy blog—and my hope that a few readers might find my posts as entertaining and valuable as I regularly find his.

Comments

[steve sturm]

1 - isn't there a fair amount of subjective analysis when you're assessing what sections apply to health and safety?
2 - can't the regulations be gamed by drafting them to include as many health and safety key words as possible? (I think this would be logical outcome if your system was adopted, licensing boards would revamp the regulations so everything was in the context of health and safety, in the same way lots of social spending is done 'for the kids'.
3 - what's the basis for measuring the health and safety portion of a regulation? Is it word count? Is it number of sections, sub-sections, etc.?

[DaivdBehar]

Does a high score on a test of health and safety correlate with fewer accidents in cosmetology? You have to do that analysis from the records, then in the field. If a correlation is found, are both an effect of general intelligence and not of the training?

hard work, but more valid than the inscientific garbage peddled by the toxic lawyer profession today.

[DaivdBehar]

"And I will close by expressing my gratitude to Eugene Volokh both for letting me post a few thoughts here and for providing many hours of fascinating reading over the years through the Conspiracy blog—and my hope that a few readers might find my posts as entertaining and valuable as I regularly find his."

I don't see how one can address professional training quackery without addressing the rent seeking theory. In that theory, one collects money at the point of a gun, and one returns nothing of value. The theft is hidden in the higher fees to the public for no additional value. This may be a heist of over 20% of the economy, and is the biggest crime of the toxic lawyer profession, the enforcers of rent seeking. The sole validity of these quack rules are men with guns, arresting violators.

[DaivdBehar]

The students can have 1000 hours of safety training. It will not make any difference to safety. When they cut hair, the supervisor showing them what must be done, correcting mistakes, and repetitions are what will enhance safety, not class time.

[Rossami]

From the description of the methodology above:
1 - yes, there's a subjective component to the analysis
2 - no. First because this an an analysis of the field's textbooks, not the regulations. Second because this is a retroactive analysis of those texts already published, not a proposal to use this methodology to evaluate regulations (or texts) going forward.
3 - as I understand the methodology, 'if safety-related keywords found in the section, page count of the section'. Or possibly the sub-section.

[Michael P]

This level of detail and discussion is great -- it really helps explain the basis for your argument, and it reflects both your level of care in this analysis and how seriously you take being open and clear.

I would suggest two reasons that this approach may lead to a too-low estimate of what portion of training is defensible on public policy grounds.

First, the health and safety sections of a textbook seldom stand alone. They rely on background facts that may not be obvious or entirely clear to laypeople. For example, knowing chemical X requires certain precautions does not mean the student knows what chemical X should be used for, what alternatives exist, and what the trade-offs of X versus Y. Those factors all guide safe use of the chemical.

Second, a lot of cosmetology is hard to reverse -- one cannot un-cut hair. Determination of marginal skill and reputation, and trading that versus price, is ultimately the consumer's decision; however, ensuring a minimum level of competency protects the public from unpleasant, and long-lasting, surprises. This could be handled by private organizations, but the public would then need to know the reputations of those organizations to distinguish a high-quality recognition from a low-quality one.

If one accepts these arguments, it would marginally affect the reasonable cap on training duration, mentioned in your post yesterday. Instead of a 300- or 400-hour limit, it might be 500 or 600 hours. The minimum-skills component is hard to quantify; someone with pre-existing talent and interest in the field would not need much extra work, but a mediocre student would need more guidance and practice. In this respect, that kind of ceiling should be a threshold for allowing people to test for readiness, not a hard limit on training.

[David Nieporent]

I would suggest two reasons that this approach may lead to a too-low estimate of what portion of training is defensible on public policy grounds.

I would suggest a reason that the opposite is the case: It treats all training purportedly relating to safety as defensible on public policy grounds.

1) Sanitize your equipment.
2) Don't mix the wrong chemicals together.

There; I just summarized the safety training. What's that, eight hours at most when fleshed out? Maybe there are a lot more complicated chemical issues than I realize, and it requires a whole week. Seems unlikely, but IANAC. But the notion that hundreds of hours are required is laughable.

You know how I know? Because licenses actually related to safety require far less. One can obtain a pilot's license with a few dozen hours. To obtain a commerical pilot's license requires a few hundred hours. (To be clear, that's not sufficient to get a license to fly an airline's planes; that's for flying people in small planes.) It requires fewer hours to become an EMT than the safety-related training required for cosmetologists. Does anyone think the health issues confronted by cosmetologists are more complex and more serious than those confronted by paramedics?

[MatthewSlyfield]

"Second, a lot of cosmetology is hard to reverse — one cannot un-cut hair. "

Hair grows. Given sufficient time it will un-cut itself.

Almost nothing in cosmetology is genuinely permanent. There may be things that can't be deliberately un-done now, but it will all un-do itself eventually.

[VinniUSMC]

There are some things, like chemical burns, which might be a little more than just screwing up hair. But, those are the things that health/safety training is for.

Training for keeping up with trends, that should just be seen as continued education for a stylist, not a barrier to entry.

[MatthewSlyfield]

"There are some things, like chemical burns"

I can't find any statistics on it, but while it does happen, I would expect that chemical burns severe enough to cause scaring or other permanent disfigurements are quite rare.

Aside from licensing and training issues, salons can be sued for causing such injuries and most salons would likely be bankrupted by only a couple such lawsuits.

[Rossami]

I dispute your second point (that a lot of cosmetology is hard to reverse). You are right that you can't uncut hair. On the other hand, it grows back relatively quickly. And you can always go to another, better barber who can repair all but the worst style mistakes.

You are on stronger ground with point one (which addresses Vinni's chemical burns comment) and could be on stronger ground for appearance-industry changes that are permanent - tattooing, for example. But most cosmetology is very, very low risk. A bad haircut means I let it grow out for a couple days and maybe get another haircut sooner than I wanted.

[MatthewSlyfield]

"and could be on stronger ground for appearance-industry changes that are permanent – tattooing, for example"

Body modification practices such as tattooing are not considered part of cosmetology and are not included in either training or licensing for cosmetology.

[Rossami]

Yes, that was kind of my point.

[apedad]

". . .they are typically taught how to do so safely (for instance, you must clean and disinfect your instruments, or else you may spread disease) . . . ."

OT side note.

In 1994, I was deployed to Entebbe (you all know about Entebbe, right!), and Kampala, Uganda. It was to support a US humanitarian mission in central Africa. During the Rwandan genocide of 1994, members of the Hutu ethnic majority in the east-central African nation of Rwanda murdered as many as 800,000 people, mostly of the Tutsi minority.

Anyway, we had a local national driver, Paul (named because Pope Paul was visiting Uganda when he was born), and one day he and when went to get haircuts in downtown Kampala (UG capital).

Normal barbershop, normal process (scissors, razor on the neck).

But afterwards, I remembered something like 50% of the population had AIDS (and 100% of the prostitutes had it), and I started thinking if the barber had cleaned the razor.

Oh well, I'm still alive.

Now back to our regularly scheduled program.

[Dr. Ed 2]

The AIDS virus is quite fragile and tends to die very quickly once it is outside the body -- much moreso than other viri (e.g. Hepatitis). It also dies once it drops below body temperature, although in Kampala, absent an air-conditioned shop, ummm....

[DaivdBehar]

The Huttu genocide of the Tutsi shows how ordinary and common genocide is. All have one feature: weakness of the victims.

The same people who were slaughtered in Europe were going to be slauhgtered in Israel. They got guns. No genocide in the Middle East. All minorities should be armed, and should kill the lawyer protected scumbags coming for their lives. The killings should focus on the oligarchs. The genocide was planned ahead of the assassination of the President. The lawyers allowed it. Kill the lawyer hierarchy while killing the oligarch enemies.

It is disturbing to read about the targeting of Hamas military leaders by Israel. They are funglible employees, replaced in a second. Why is Israel not killing the oligarchs behind this attack, wherever they are, including in the Biden administration? Those thousands of rockets were financed by the $235 million Biden, also an employee of the oligarchs, sent to the enemy of Israel.

Instead of immunity of oligarchs, they should have open season on them, with full legal immunity for killing an oligarch who attacks a people.

[Dr. Ed 2]

"...chemically relaxing the hair"

Let's get real here -- that's a political mandate imposed by Black activists who wanted to ensure that *all* salons were able to straighten Black hair.

There are two sides to this as we *do* have a significant Black middle class and a lot of Black women with money to spend -- should the government mandate that *every* salon and *everyone* working there be qualified to provide a service that only they need?

Or should the market be permitted to drive specialization?

There are enough Black women with enough money to spend to ensure that *someone* will care for their hair, although it might not be the closest salon. But the flip side of this is that the place which is doing it all the time is going to inherently be very good at it, while the place that does it once a month can make mistakes...

It's the same thing with abortion and (regardless of ones position on abortion itself) it is not a bad thing to have abortion increasingly concentrated in distant cities -- morbidity and mortality increase dramatically when the place is only doing a few a month. (That's true of *any* surgery.)

Now the dangerousness of the hair relaxers is something else -- but there is no reason why that can't be an additional certification, particularly if it includes the ability to purchase chemicals that the general public isn't allowed to buy.

This is done already with truck licenses -- not all trucks have air brakes, but if you wish to drive one that does, you have to not only get a CDL but an air-brake endorsement. Same thing if you wish to drive a tanker truck.

[Dr. Ed 2]

Do we want equality of opportunity or equality of results?

Not all women have the same type of hair -- and the opposite of Black hair is Nordic hair -- blonde and with very thin strands. So do we want to insist on equality of outcome, and every shop being able to do a so-so job for every woman, or equality of *opportunity* where any woman can purchase the services offered by any shop, but the shops can explicitly specialize and only offer those services in which they specialize.

[Lee Moore]

Folk on the right tend to insist that they are for "equality of opportunity" rather than for "equality of outcome" (which I believe is now called "equity" - "equality of outcome" having become politically toxic, a new name is required for it.)

But all the arguments that righties hurl against "equality of outcome" - impossible to achieve, requires totalitarian intervention by the government even to attempt, destroys incentives etc - apply just as much to "equality of opportunity."

Of course a classical liberal government framework can avoid inequaity in formal legal opportunity (eg no sex or race etc discrimination by the law itself) but that certainly doesn't amount to equality of opportunity. We all differ in inherent physical and mental attributes, and the child of rich or well educated or competent parents will get a better start than the child of poor, ill educated or incompetent parents.

Equality of opportunity is nearly as much of a fantasy as equality of outcome. Beyond formal legal equality, the essential question is how much of Peter's liberty are you willing to rob from him, to improve Paul's opportunities ?

[apedad]

I look at equality of opportunity as ensuring minimum levels of opportunity, i.e. a floor not "minimum" as in just get by.

Rich, educated, or competent parents should be able to provide "more" opportunities to their children - while at the same time, we as a society have to ensure there's a minimum (floor) of opportunities.

Of course, some people still think Plessy was a good decision (but then their parents were neither rich, educated, or competent).

[Lee Moore]

I would tend to agree. While equality of opportunity is impossible even in theory, providing extra opportunities to those with few is not.

Though I doubt that even a floor is achievable. If you set a floor so low that someone with an IQ of 80 can get to it, it's not much of a floor.

Practically there's also the question of cascading opportunities. Seizing an opportunity is liable to generate more opportunities. Failure to seize current opportunities is liable to dry future opportunities up. But failing to seize an opportunity may result from a number of different causes, eg :

(a) you are a lazy bum and, when opportunity knocked, you preferred to stay on the sofa
(b) you were sick in hospital when opportunity knocked - you recovered just fine, but by then opportunity had moved on
(c) opportunity forgot to knock
(d) some complicated mixture thereof

Thus your lack of opportunities at age 35 may be the result of a poor socio-economic legacy and an unbroken string of bad luck, or a great socio-economic legacy and an unbroken string of real bad decisions, or any combination in between. Talk of creating opportunities for those that don't have them tends to be couched in terms of poor unfortunates who never had a chance. But in practice lots of unfortunates aren't particularly unfortunate, they have just spurned or messed up a string of opportunities in the past, leaving them high and dry now.

It's the old deserving and underserving poor thing. Maybe God knows how to sort the wheat from the chaff, but it's probably beyond us humans.

And last but not least, luck plays a role in plenty of opportunities. How do you even that up ? How do you even know how much to attribute to luck and how much to judgement ?

I don't wish to imply that there's no point trying because it's so difficult - I merely recommend a bit of humility as to how much we can know about who deserves what sort of help. Just going on who can show us some impressive sores isn't enough. Some people richly deserve their sores. Indeed some people who haven't got sores richly deserve some.

[DaivdBehar]

It never too late. For example, an addict goes into recovery at 35. She is keeping a job, meeting guys outside that world, gets married, has a child. Her addict skills, at getting people to do stuff they do not want to do, makes her a highly successful waitress with big tips. She has started a good life, just 15 years late. Perhaps, she was forced into treatment by a judge, as an alternative to prison. The legal system can make itself very useful. Now we have a productive tax payer, insead of a devastating natural catastrophe, costing $millions in damages.

[Lee Moore]

The point is not whether it is ever too late to give someone an opportunity - it's that for any given level of taxpayer funding, or restriction of Peter's liberty, government created opportunties are a limited resource.

Who should get the next opportunity ? If you give a 35 year old addict her 23rd opportunity, there's somebody else who is not going to get that opportunity. What's the basis for deciding ?

- Mr A "deserves" it because he tries hard and hasn't spurned previous opportunities

- Ms B ought to get it because although she's spurned 23 previous opportunities, if she grasps this one then it will have a big social payoff

- Ms C ought to get it because although the social payoff will be rather modest, statistics show that people like Ms C tend to grasp this sort of opportunity much more often than the Ms Bs grasp theirs.

There is of course another option - everyone should get another opportunity ! No one should be left behind ! The rich should pay more ! But though this creates warm and fuzzy feelings in children of all ages, it's ....childish.

From the point of private charity or religious mission, there's much to be said for giving opportunities to people however unlikely they are to grasp them. From the point of view of the taxpayer however, it's a waste of money. And by a waste of money I mean that robbing successful Peter of his opportunities is likely to hurt others in society apart from Peter himself. Like Peter's customers, suppliers and employees, now and in future.

[Krayt]

The use of termd like equality of outcomes or equity already eviscerates the reason for freedom -- to be free...from government oppression, which includes corruption. Indeed, corruption is the porpose of dictatorship, and why people go into government, dictatorship or free nation.

How many millenia have people just dreamed of living free? Free from having to get on bended knee for permission to do things, to pay ransoms on freedom, later renamed taxes on the euphemism treadmill?

The impetus to corruption is there still. These "feel good" regulations are 90% corruption and 10% use, purely coincidental, as with the stopped hands on a clock.

By allowing this goalpost shift, you are already in the corruption bathtub, puzzled why you are still covered in filth no matter how hard you scrub.

[jdgalt1]

Agreed. The same mindset that demands all barbers be able to straighten a black person's hair has in some places demanded the abolition of men's barber shops in favor of unisex hair stylists that charge men and women the same, even though (most) men's hair cuts are much simpler. Such laws do not serve the public interest; they amount to minimum-price laws for the sake of equal outcomes, and people find ways to evade them.

The same goes for laws like the "Equal Pay Act" which amounts to demanding that women be paid the same for working fewer hours.

[bernard11]

morbidity and mortality increase dramatically when the place is only doing a few a month. (That’s true of *any* surgery.)

So you're fine with preventing rural hospitals from doing appendectomies?

Can't travel? Too bad for you.

[Lee Moore]

that argument would have some eyebrow-raising implications for the training of appearance professionals

Very good 🙂

As to your question - no, I'm not very convinced by the method. To start with, I'm not convinced that what gets into textbooks is "just the facts, Ma'am" - lots of people have a line to push, whether commercial or political, and textbooks are a good place to push lines.

But you might self test your own method a bit. At first glance there look to be several rather subjective line calls you get to make in constructing your mathematical model. My suggestion is - imagine you are a bad actor and want to use your method to push a particular viewpoint eg

(a) that there's not much health and safety content, and most of the regs are just there to order people about pointlessly

and then see how far you can tweak your own linecalls in your model to achieve a result that bolsters that viewpoint. Then redo to exercise to arrive at the opposite viewpoint -

(b) that there's lots of useful health and safety stuff there

and see if you can get your method to support that view, by tweaking what is tweakable in your method.

If you find that you can make your method sing pretty much any tune you like, then your method sucks.* If you find you can't, then it may still suck, but it will suck in a non biased way.

* this is the standard method for most social science models. The answer is inherent in the model's assumptions, which assumptions have been carefully constructed so as to arrive at the right answers.

[Lee Moore]

A good illustration of constructing a flexibly tweakable model was from a couple of years back when some ferociously feminist researchers wished to demonstrate that human brains were not sexed - ie you couldn't tell by neuro-imaging whether you were looking at the brain of a man or a woman.

Their math was excellent, and their result - showing that you couldn't tell the difference - was published and ballyhooed around the world.

But when other folk started looking at their results, eyebrows were raised (TM.) It turned out that they had cunningly constructed their models so that these counted lots and lots of datapoints that did not differ between males and females, and the effect was to swamp the few datapoints where there was a (statistical) difference.

So it was like doing an analysis of male and female bodies and including a few things things for which there is a (statistical) sex difference - eg number of penises, voice pitch, but swamping these with things for which there is no sex difference - like - number of toes, number of fingers, number of ears, whether nose is above or below eyes, ratio of thumb length to big toe length, number of kidneys and so on. If you add in enough of this sort of datapoint, you're bound to arrive at "look folks, no significant difference."

But other researchers, using different datapoints, rapidly found they could identify whether a brain belonged to a man or a woman with 80% accuracy. And when some Japanese scientists went full nerd on the question, they found they could get up to 95% accuracy.

A social science model is much like a government inquiry. You can tell, in advance, what a government inquiry is going to find by looking at who appoints the members of the inquiry team. Likewise you can tell, in advance, what a social science model is going to find by looking at who constructed it.

[apedad]

Good thing we have peer review.

[Lee Moore]

🙂 The original paper had no difficulty is leaping over that hurdle. The journal picks the peers as the government picks inquiry members.

[Don Nico]

But don't count on it especially if the editors are corrupt.

[mulched]

The content analysis approach is a good potential proxy for health and satety content, but would be more convincing if it was validated in multiple dimensions.

First, I'd validate it against an "on the ground" measurement of time spent in class and practicum on safety. Take a stopwatch, start and stop when safety is mentioned.

Second, I'd validate it against other topics in the curriculum. Do other topics evaluated using content analysis return realistic results? Does the total of all topics sum to 100%?

Third, I'd validate your process against another field, like welding, that would have a substantial safety component taught alongside their content.

[Bill_]

First off, I don't have a better method, and it's great that you are looking for quantitative means to analyze this.

I think one problem with using textbook content length as a proxy is that instructors don't always cover an entire textbook when teaching a class. They omit chapters.

So I think it's probable that when you calculate (safety)/(total content), either the numerator or denominator (or both) are too large. I'd hope that the omitted parts are non-safety, so that the actual safety fraction is larger than what is calculated.

[bernard11]

I think one problem with using textbook content length as a proxy is that instructors don’t always cover an entire textbook when teaching a class.

This is my criticism as well, and I think it is damning. The emphasis instructors place on a topic does not, as a rule, match the space devoted to it in the textbook. Drawing conclusions about percentages this way is silly.

[David Nieporent]

I would think that would be more damning in an academic subject. This is vocational training. These are not educators trying to creatively reach the students and get them passionate about a subject so that in the future they'll be good, e.g., math students. They're completing a regulatory checklist. The 'textbooks' obviously have to be used in many states, with different requirements, so they can't match any one state's particular curriculum exactly, but I doubt the instructors are implementing creative ideas about what topics to cover and how.

[bernard11]

Sure, but there are going to be degrees of emphasis. Plus, since the textbooks, as you say, will be used in many states they will have to cover things that are not emphasized, or maybe even taught, in some states.

I don't think it's hard to imagine that any given state's checklist is met by, say, 70% of a given text, though not the same 70% everywhere. Now, say the critical stuff, which every state requires, is about a third of the textbook material. Then Greenberg's method says a third of the time is spent on the critical stuff, wheres in reality it's 50%.

Practicum is tough to measure also, because the time will vary across students. If the instructor sees a student being meticulous about safety and so on she may spend more time on styling technique, say. OTOH, the sloppy student gets yelled at, and probably ends up spending more time on safety.

[Anna V]

Not being a cosmetology instructor, let me try to see how this method would work on my Statistics course.

Let's say that the goal is to estimate what proportion of the hours of instruction is devoted to training to work on real datasets. By your measure, that would be at most 10%. However, my class time is approximately evenly split between theory and practice. Furthermore, over 90% of assessment of student knowledge requires them to demonstrate proficiency using real datasets.

This example demonstrates the limitation of your method.

All quantitative methods have limitations, of course. I would suggest that one better method would be to examine the instructor's assessment materials--what are the students actually required to demonstrate, in order to pass the course. (I don't know anything about cosmetology certification; do the students even have to pass some kind of tests?) If cosmetology courses have grades--what proportion of the grade depends on students demonstrating proficiency in safety?

[Bubba Jones]

yes, and no. This is a predictably academic analysis of a trade which could not possibly be further from a legal profession.

I would expect and hope that the safety aspects would be practiced, supervised and reinforced during the technical training.

So, you'd "learn" the safety aspects in the textbook, and then you'd apply them and improve them in the training session. And likely make mistakes along the way.

So if your textbook analysis shows 25%, you should certainly extrapolate that same percentage to the practice hours.

[bernard11]

I would be interested in hearing from readers, in the comments, whether they view the article's method for estimating the health and safety portion of appearance professional training as well-grounded—and, furthermore, whether they can think of a better method for this kind of measurement.

I do not think it is well-grounded. There is no necessary correlation between space taken in the textbook and time spent in class, or in supervised practice - whatever it's called - on any topic.

And, as I said in an earlier thread, I don't think the percentages so derived would be particularly useful, even if they were accurate.

[Rossami]

I think that page count alone is a modest proxy for training focus or hours. It may be the least bad choice available but I fear that it could be subject to skewing. Consider, for example, your chemical hair relaxing section. I would imaging that much of the text book consists of reference tables. Lists of specific chemicals and potential interactions. Things that you should know exist but which the student is not expected to memorize.

By analogy, think of a comprehensive math text that has both a description of the concepts of trigonometry (and the supporting problems and homework) with all the trig tables. Those tables are an essential tool (for anyone without a calculator, at least) but they do not represent learning time. Sometimes those trig tables are published as their own independent text (a better approach in my view) but there are credible reasons why publishers might choose to include the reference materials in the same textbook.

To the extent that your appearance professional texts included such reference tables and resources, you may have introduced some systemic bias to your allocation of training hours.

[AmandaGreen]

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