The $30 Million Assumption Nobody Checked
A case study in unexamined policy, upstream thinking, and what it actually costs when nobody checks the ground.
Every spring, schools send kids home based on a policy nobody thought to question.
That sentence is the starting point for what I now call an Assumption-Ground Audit — the practice of tracing an assumption back to its source before it hardens into strategy, policy, or irreversible action. Most of the time, organizations skip this step. They inherit the assumption from the policy before them, or the vendor who recommended it, or the industry norm that nobody remembers creating. They act on it as if it were settled. It isn't always.
The story below is a personal one. It involves lice. I'm warning you now: it is impossible to read about lice without a psychosomatic reaction, and I am sorry. But it is one of the clearest examples I have of what an unexamined assumption costs — in time, in stress, in a child's mental health, in a parent's employment — and what happens when someone finally decides to check the ground it's standing on.
The central assumption was this: lice are a health risk, therefore children with any evidence of lice must be excluded from school.
It felt like fact. It was policy. Nobody had verified it.
Sometimes it can be useful to recall how far you've come. In 2012, I was a year into a new high-pressure, high visibility job and I broke my foot and was off work for two months. The work from home pilot had been suspended to review the impact on productivity. My kids were 3 and 5 at the time and did not know the word slow. They were runners, especially my oldest. I limped after them the best I could. Then the strikes happened which meant more time off work. Spring 2013 brought lice….and chaos. I took a whole week off to wash everything in the house. My manager at the time had beautiful curly hair and was extremely empathetic to my situation. I'm still very grateful. However, once the girls went back to school, they were sent home constantly. 7 times over 6 weeks. When we talk about barriers to women in the workplace, your kids being sent home consistently when you work over an hour a way from home with limited family support is definitely one. My husband is a contractor so he cannot leave someone's house ripped apart to be able to stop work and pick up the kids. And as supportive as he was, he was bald. His solution was to shave his head; my reality was that the school vice-principal checked my head to make sure that I was not a carrier and the source of the pediculosis. Completely mortifying. Fortunately, bright white hair makes it very easy to spot infestations…. something I never knew would be a blessing. Thankfully, I never had lice personally.
So to set the stage of what our family life looked like in April 2013, I had two traumatized girls who cried when I approached them with a comb, a house that was ripped apart and covered with plastic while trying to work 8 hours a day with a 2-hour commute. We consulted doctors, nurses, companies that specialized in removing lice. It makes me sick to know how many chemicals I applied to my girls' heads before I understood that lice were resistant to the treatments. Superbugs are a thing. We had limited family support and the babysitters understandably had to consider the other kids and parents. I don't know if I can adequately express the stress level we had in the house. The seventh time my girls were sent home, I lost it. I told the school that they could not continue to send the kids home. They had been properly treated but by that point, their scalps were so tender, they had dandruff. The school had a parent volunteer in charge of checking hair, and she could not identify dandruff versus nits (eggs of the lice). The school told me the policy in place allowed them to send the kids home if there was even a risk of nits and they could do it as often as they wanted. There was nothing in the policy that allowed parents to challenge the impact on education or mental health of the affected children. They didn't care that there could be an impact to my employment if I continued to take time off. The policy trumped all other concerns. If I had a problem with it, I could speak to public health. I spoke to public health who told me that the school board policy was punitive and that lice was a nuisance, not a health risk, and they wished someone would change the policy. I now had a solution. All I had to do was change the policy. Sounds easy? Ha, no.
At the heart of it, a school board is a bureaucracy, so you must understand how it works. Working in financial services means that you get pretty good at reading and interpreting policy. Back then, all school policies were public and posted on the website. Now they are accessible only to board employees unless individual schools post them to their own website. Every night after I got my kids to bed, I would research pediculosis. It is not a fun topic. It is full of drama – anything that people fear brings out the worst in people. To win my battle with the parent volunteer, I studied the lifecycle of the louse. I started to track when the girls had been declared clear and when she checked them again. I started challenging the school if they sent them home before a nit could possibly have been created. I won these arguments because I used reliable facts presented in an unemotional manner and countered that if they didn't concede, I would challenge their science curriculum. The school board is responsible for teaching children science and lifecycles are part of the elementary school curriculum. I worked to gain the support of the principal, the superintendent and the school board trustee. The principal was not useful but the superintendent was amazing. She explained school board protocol, how policies are created and reviewed, explained the internal politics and agreed to support me. She provided me with her personal cell phone number and connected me with the person responsible for reviewing policies. The superintendent did an exceptional job of representing the school board but also making me feel like my concerns were being taken seriously. Leading with empathy and compassion were very evidently the reasons she was so successful at the school.
I owe an awful lot to a stranger in Nevada. My research led me to a school nurse in Las Vegas who changed the pediculosis policy for the state. She had written a paper about the process, but it was behind a paywall. I found her contact information and asked her if she would help me. She agreed to explain how she had changed the policy in Nevada if I explained where I found her contact information. My investigation skills got me the information I needed, and she was able to have her contact information removed from the site I used to find her. The nurse led me to the pediatric societies. All pediatric societies of the western world have public pediculosis policies. The United Kingdom, the United States, Australia, New Zealand and Canada all have policies that state that live lice must be treated but kids can and should be allowed to attend school with nits due to negative impacts on mental health and education.
This is the wording from the Canadian Pediatric Society document (caringforkids.cps.ca):
Children with head lice should be treated and then attend school or childcare as usual. 'No-nit' policies that keep children with head lice or nits after treatment away from school are not necessary.
It took me 18 months of ongoing work with the board to craft a policy that addressed the need to treat the live lice but allow attendance with nits. I provided extensive documentation about the impacts to mental health as a result of "no-nit" policies. Essentially if anyone tries to counter the policy, they would have to argue why they are right but all the pediatric experts in the western world are wrong. I'm very proud that several of the pamphlets I provided to educate staff and parents alike are still being distributed as resources to back the policy. York Region Board of Education served 98K families back in 2012; now it's 128k. Although I hope your kids never get lice, if they do, you are protected by the policy I helped craft.
For me personally, this process taught me the real value of the skills I brought to work every day: critical thinking, advocacy, empathy, compassion, communication, research, writing, resilience, persistence, determination, relationship building, adaptability, negotiation skills, and change management.
I taught my girls that if there was a serious problem, I had the skills and ability to do something about it. To this day, I now teach them to self-advocate by asking them if they want to handle it or if I must do it. Because they know that if I step up and speak to the school, things will change. We review the issue and most of the time, they decide that they can handle it. It's very useful for teaching them about their own power. My mother taught me that the best thing a parent can teach is independence and to lead by example. It's always my goal.
I've shared this story every spring since 2015. Lice season is real, the policy still matters, and every year someone tells me it happened to them too. The original version was published on LinkedIn in February 2020.
That's the personal story. Here's the methodology it produced.
What Is an Assumption-Ground Audit?
An Assumption-Ground Audit is a structured process for tracing a belief, policy, or strategy back to its original source — before it hardens into irreversible action. It asks: what are we taking for granted here, who decided it was true, and has anyone actually checked? The audit is upstream work: it happens before the decision calcifies, before the vendor contract is signed, before the seventh time someone gets sent home.
What an Assumption-Ground Audit Actually Looks Like
Let me map what actually happened.
The assumption: Lice — specifically nits, the eggs — constitute a health risk sufficient to warrant repeated exclusion from school.
Who held it: The school board, the parent volunteer, the policy itself. Not maliciously. The assumption had simply never been examined. It was inherited, codified, and enforced. The people implementing it had no reason to question it because nobody had asked them to.
How long it had been treated as settled: Long enough to become board policy. Long enough that the school's response to my challenge was: this is our policy, speak to public health. Long enough that public health — who knew the policy was wrong — told me they wished someone would change it, as if that were a thing that happened to other people.
What auditing it actually revealed: The pediatric societies of the United Kingdom, the United States, Canada, Australia, and New Zealand had all already done this work. Every one of them stated clearly: live lice should be treated, but children with nits should attend school. The Canadian Pediatric Society is unambiguous: "Head lice don't spread disease. They are a nuisance and unpleasant, but they are not dangerous." The assumption had no scientific ground. It had never had ground. The evidence existed. Nobody at the school board had gone looking for it.
What it cost while it went unexamined: Seven removals from school over six weeks. Two traumatized children who cried when they saw a comb. A parent a career risk away from a serious employment consequence. Chemicals applied to children's scalps for a problem those chemicals couldn't solve. Eighteen months of after-hours work to fix a policy that should never have been written the way it was.
The Outcome
My daughters haven't had to navigate this since Grade 2. That's the personal result. But the policy I helped craft in 2015 didn't just protect my family.
York Region is one of the fastest-growing regions in North America. The board served 98,000 families when this started. It serves 128,000 now — and that number keeps climbing. So run the math. Clinical prevalence of lice in school-age children runs 6-12% per year. Conservatively, that's roughly 6,000 cases per year in York Region's elementary population alone. Under the old policy, each case generated multiple wrongful exclusions — mine generated seven over six weeks. Each exclusion costs a parent a minimum of four hours: travel, pickup, childcare scramble. Add the cost of treatments that couldn't work because the lice were already resistant to them. Add the professional removal services families paid for out of desperation.
Per case, conservatively: $390 in direct losses. Multiplied across 6,000 cases per year. Over eleven years of a corrected policy applied to a growing population.
One audited assumption. One corrected policy — improved in 2019. Roughly $30 million in direct economic value — and counting.
That's before you account for educational disruption, the mental health costs of repeated wrongful exclusion, or the families who didn't have to choose between their child and their employment because someone finally checked whether the assumption had any ground.
It didn't.
The procedure that resulted — Board Procedure #662.11, revised 2015 — mandates that every family with an affected child receives the Canadian Pediatric Society Head Lice Facts document. That document is Head lice | Caring for kids, published at caringforkids.cps.ca. It's the same document I found during eighteen months of after-hours research and presented to the board as the evidentiary foundation for the policy change. It is now standard procedure. It goes home in a child's backpack every time a case is identified, to families who have no idea it was ever in dispute.
The research didn't just inform the policy. It became the policy's evidence base — permanently embedded, distributed at scale, cited by name in a binding board procedure.
And the policy kept getting better. The 2019 revision went further: the head-checking requirement was removed entirely. The parent volunteer role — the one that couldn't distinguish nits from dandruff, that sent my daughters home seven times — was procedurally eliminated. For nits, the 2019 procedure is a single step: send home the CPS document. No treatment form. No exclusion. No examination. For live lice, the school no longer manages treatment at all — families are referred directly to Public Health. The burden shifted out of the school entirely.
That's what good policy design produces. When you build policy on audited assumptions, grounded in evidence, with human experience at the center, it doesn't just fix the immediate problem — it creates conditions for continued improvement. The 2015 change set the trajectory. The 2019 revision took it further. Policy built on unexamined assumptions drifts further from reality over time. Policy built on evidence, oriented toward the people it affects, gets better.
The Question Your Organization Needs to Ask
I work upstream. By the time I was arguing lifecycle science with a school vice-principal, the damage was already accumulating. The Assumption-Ground Audit is what happens before the seventh time someone gets sent home. It's the question asked before the policy is written, before the strategy is committed, before the vendor contract is signed: what are we taking for granted here, and has anyone checked whether it's true?
The pediatric societies had done the work. The ground wasn't there. Nobody checked.
Your organization has policies built on assumptions that have never been audited. Some of them are fine. Some of them are costing you in ways you haven't named yet — in dollars, in talent, in time, in trust. The question isn't whether the assumptions exist. They always do. The question is whether you examine them before the seventh time.
Or after.
That's what upstream work produces. Not a visible win — a problem that never happened, at scale, for people who never had to know the fight existed.
If you recognized your organization in this story — in the assumption nobody checked, the cost nobody counted, the seventh time that didn't have to happen — that recognition is data. The Assumption-Ground Audit is what you do with it.
What the AGA is and how it works →
A Note on the Math
The $30 million figure is a conservative estimate based on two policy revisions, each of which eliminated a distinct layer of wrongful exclusion.
Population base: York Region District School Board serves approximately 128,000 families. Lice primarily affects elementary-age children (K-6), approximately half the board population, averaging roughly 75,000 students over the policy period.
Prevalence rate: Clinical studies place lice prevalence in school-age children at 6-12% per year. This estimate uses 8% — the conservative midpoint — yielding approximately 6,000 cases per year.
Cost per case under the original policy:
- Wrongful exclusions prevented per case: 2 (this is the assumption doing the most work in the model; real-world cases likely range from 1 to 7+, and my family experienced 7 over 6 weeks — 2 is the floor, not the average)
- Parent time lost per exclusion: 4 hours minimum (travel, pickup, childcare arrangement)
- Blended average Ontario wage: ~$30/hour
- Lost wages per case: 2 × 4 × $30 = $240
- Unnecessary treatment costs (over-the-counter products, professional lice removal services): ~$150
- Total direct cost per case: ~$390
2015/2016 revision — aggregate calculation: 6,000 cases × $390 = $2.34 million per year Policy in effect 2015–2019: 4 years Subtotal: ~$9.4 million
What the 2019 revision added: The 2016 policy corrected the foundational assumption but left the implementation mechanisms in place — head checks before readmission, treatment forms, and a parent volunteer role that could still generate wrongful exclusions. The 2019 revision eliminated all of it. For nits: one step, no exclusion, no examination, no paperwork. For live lice: refer to Public Health. The remaining friction under the 2016 policy conservatively generated one additional wrongful exclusion per case that the 2019 revision eliminated.
- Additional exclusions eliminated per case: 1
- Value per exclusion: ~$120
- Additional value per case: $120
2019 revision — aggregate calculation: 6,000 cases × $120 = $720,000 per year Policy in effect since 2019: 6 years Subtotal: ~$4.3 million
2016 policy continuing value post-2019: 6,000 cases × $390 = $2.34 million per year × 6 years = ~$14 million
Combined total: ~$27.7 million — call it $30 million when rounded conservatively upward to account for population growth.
This figure excludes: educational disruption and its downstream effects, mental health costs associated with repeated wrongful exclusion, employer costs from unplanned parental absence, staff time previously spent managing a medical nuisance schools were never equipped to handle, and the compounding impact of York Region's continued population growth — one of the fastest rates in North America — which adds families to the protected base every year.
The number goes up, not down, when you account for those variables.
But here's what the dollar figure doesn't capture, and what matters more.
The parents dropping their kids off this morning in York Region have no memory of this fight. Neither do the kids. The policy just exists, the way good infrastructure exists — quietly, doing its work, protecting people who never had to know it was built. The family who moved to York Region last year, whose kids weren't born yet in 2015, walks on that ground without knowing it was checked. They just get to have a better experience. Their kid doesn't cry at the sight of a comb. They don't get a call at work they can't afford to answer. They don't spend a week washing everything they own chasing a treatment that was never going to work.
The $25 million is real. It's a proxy for prevented damage at scale. But the actual outcome is simpler: families who never had to go through what we went through. That's what the assumption was costing. That's what auditing it gave back.
Upstream work is invisible by design. The best version of it means nobody ever experiences the problem it prevented. Nobody counts the seventh time that didn't happen. There's no credit, no memory, no record of the counterfactual. Just the quietly better experience of people who never had to know the fight existed.