Everyone interested in understanding how the ceaseless pressure to raise test scores can corrupt the tests should be familiar with Campbell’s Law.
This is an adage written by social scientist Donald T. Campbell in a 1976 paper. It says:
“The more any quantitative social indicator is used for social decision-making, the more subject it will be to corruption pressures and the more apt it will be to distort and corrupt the social processes it is intended to monitor.” (You can google the paper, or find it linked on Wikipedia: Campbell, Donald T., Assessing the Impact of Planned Social Change The Public Affairs Center, Dartmouth College, Hanover New Hampshire, USA. December, 1976.)
Campbell’s Law explains why high-stakes testing promotes cheating, narrowing the curriculum, teaching to the test, and other negative behaviors..
In his 1976 paper, Campbell also wrote that “achievement tests may well be valuable indicators of general school achievement under conditions of normal teaching aimed at general competence. But when test scores become the goal of the teaching process, they both lose their value as indicators of educational status and distort the educational process in undesirable ways. (Similar biases of course surround the use of objective tests in courses or as entrance examinations.)”
Campbell’s Law helps us understand why No Child Left Behind and Race to the Top are harmful to education. They put pressure on teachers and principals and school districts and states to get higher and higher test scores. As we saw in Atlanta and in Washington, D.C., this kind of pressure may cause educators to betray their ethical duty by changing test scores. As we saw in New York state, this kind of pressure may cause a state education department to lower the passing mark on state tests so as to boost proficiency rates.
As high-stakes testing has become the main driver of our nation’s education policy, we will see more cheating, more narrowing of the curriculum, more gaming of the system. None of this produces better education. And even the test scores–on which so much public policy now firmly rests–will be corrupted, by making them so important.
Diane Ravitch's blog 
I wonder how many other teachers have been pressured by supervisors to find “a few extra points,” on a New York state regents exam? I’ve certainly seen it happen.
Absolutely. “Lead us into temptation” but then punish us when we follow. The same rules apply with respect to every social policy.
A slight variant is Wildavsky’s Law, “Movement on any indicator can be maximized provided society is willing to ignore all other indicators.” Aaron Wildavsky, Speaking Truth To Power: The Art and Craft of Policy Analysis. Transaction Publishers, 1987. Page 31.
I like this one because it emphasizes that fetishized indicators will go wrong even in the unlikely case that there is no corruption.
Unfortunately, Campbell’s Law is based on Murphy’s Law: If anything can go wrong, it will. And remember O’Toole’s Commentary on Murphy’s Law: Murphy was an optimist.
I think it was management “guru” (notice the religious connotations) Peter Drucker who said, “That which can be measured, can be managed.” So we are talking about power and control here, masked by the trappings of “science:” the re-ordering of teacher labor relations and classroom practice, as defined and determined by those who control the metrics and the assumptions that underlie them. That is one unspoken (for public consumption, anyway) facet of high stakes testing.
On a more insidious level, the pressures placed on teachers and public schools by high stakes tests are intentional: the tests are a weapon to undermine tenure and seniority, create a climate of fear and intimidation, close schools, privatize them, and turn teaching into temporary, at-will employment subject to the voracious appetites of market players. Temporary, constantly churned employees (a la TFA) cannot provide the institutional counterweight to school privatization that career, civil service, unionized teachers can. Thus, the constant attacks on teachers and their unions.
When, as per Campbell’s Law, the inevitable cheating occurs, yet another avenue for attacking teachers opens up. It’s a perpetual motion machine for undermining the schools and teaching as a career, leading to “proof” that the public schools and their teachers are failing, and must be replaced.
Needless to say, this also opens up a gold mine for all sorts of parasitic testing companies, publishers, curriculum developers, consultants and corporate hit men.
Who says there’s no money in education?
Test scores are for education what body counts were to winning in Vietnam.
Alas, too few administrators, and almost no state legislators, understand Santayana at all.
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I think a lot of people take “corrupt” in this context to mean legal or ethical misdeeds – such as cheating on tests, and so on. The typical response to that is to tighten up on security and discipline, with more money spent on controls and more serious penalties for infractions.
But that’s not the point. What Campbell meant by “corrupt” was that the tail would begin to wag the dog: some indicator, chosen because it was measurable but indirectly related to some broader phenomena of interest (that was hard to measure), was useful as long as the indicator itself did not drive consequences for people or groups. However, if the movement of that indicator starts to have severe consequences for people, they react rationally (!) by changing their behavior to move the indicator in a beneficial direction.
The problem comes because the indicator – in this case, standardized test scores – was only indirectly related to the variable of interest – a successful education. When high stakes consequences are attached to the indicator, the changes in behavior that it drives breaks the relationship between the indicator and the original background variables of interest. The indicator, test scores, drives behavior that will increase test scores but may or may not lead to any changes in the underlying phenomenon we care about – a quality education. In fact, in this case we have clear cause to worry that increased time and effort spent on test preparation will come at the cost of other facets of education that we value but which are not captured with the tests.
In the physical sciences, you don’t have to worry about your indicators changing the underlying behavior (except in quantum mechanics, but that’s a different story). But when people are involved, they react to how they are measured. That’s why you need to be both very careful and very sophisticated in how you measure people in ways that carry consequences. Unless the thing you’re measuring is the only thing you care about, you’re skating on thin ice if you use a simple measuring stick to gauge something much more complex.
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