Lies, Damned Lies and Statistics

Every cancer patient is bombarded with statistics about survival rates, and “high risk” patients get the short end of those statistics. Instead of giving those numbers too much power, we need to remember what’s really behind them and how they apply to an individual patient.


I was recently reminded of an important lesson about statistics that applies to multiple myeloma. Interestingly enough, I was reminded of the lesson sitting in a stadium full of soccer fans, of all places. While a reg­u­la­tion soccer match is 90 minutes long, the official time is kept by the referee and he or she can add a few minutes to every match to compensate for the time play was stopped for injuries or other reasons. In the 93rd minute of the last game of the regular season, the Seattle Sounders scored a goal that shattered statistics.

The regular season of Major League Soccer (MLS) starts in early March and ends in late October. Like many American sports, the regular season is followed by a playoff to declare the final champion. The Sounders won the championship in 2016 and played in the championship match, but lost, in 2017. The Sounders have ad­vanced to the playoffs all 10 years they’ve been in the league, but in 2018 it appeared this streak would come to an end.

When the 2018 season began, the team’s star forward suffered a season-ending injury in the first match. Clint Dempsey, arguably the greatest American soccer player ever, retired mid-season after barely getting on the pitch in 2018. Losses piled up early. Some close games were given away, some matches weren’t even close. It seemed the season was lost before it really got going.

There are several organizations that compile sports statistics that track soccer teams’ successes, and failures, game-to-game. The numbers are used to project a team’s likely finishing position. In June, about mid-season, the Sounders had the worst record of 23 teams and were given only a 1.67 per­cent chance of making the playoffs in 2018. From my vantage point, that number seemed generous. The team looked terrible.

Many loyal fans, even in my household, wrote off the season. All objective in­for­ma­tion before us suggested the team was going to finish the season outside of the playoffs. It wasn’t a matter of giving up hope; looking at all the facts, this seemed like the only reasonable conclusion.

In July, the Sounders started winning matches, and by the end of October, they turned in the best half-season of soccer in MLS history. They not only qualified for the playoffs, but with the goal scored in the dying minutes of the last game of the season, they finished with the fourth-best record in the league.

The Sounder’s playoff games begin on November 4 (likely before this column is published). The statisticians give the Sounders only a 9 per­cent chance of winning the championship. Given what I learned this year, I’ve decided to ignore the numbers and just enjoy the games.

As myeloma patients, we’ve become pretty familiar with statistics. There are numbers everywhere we look. Every treat­ment comes with a spread of numbers suggesting how many patients might respond to a given treat­ment, how likely the response will be com­plete and whether or not the treat­ment might, in comparison to other treat­ments, extend a patient’s pro­gres­sion-free and over­all survivals. Of course, we are all familiar with some of the grim statistics regarding the number of months or years a myeloma patient might ex­pec­t to live, re­gard­less of treat­ment. As I’ve discussed in other columns, I’m con­sidered a “high-risk” patient, and the statistics for the group of patients that share my chromosomal ab­nor­mal­ity are not very cheery.

Cancer patients are often warned against giving too much stock to statistics, and for good reason. The statistics we see are merely summaries of a collection of data from a set of patients within a given category. Even within the measured collection, some patients did better and some patients did worse than the final averages and medians. There are numerous factors that influence how relevant any given data might be to our own particular case. As a single example, when discussing the over­all survival of myeloma patients, one factor that can skew life ex­pec­tancy statistics is the vast number of treat­ments that have been introduced in the last 10 years.

I’m not questioning the accuracy or validity of statistics. Statistics are critically important to researchers and doctors that are making long-term decisions about caring for myeloma patients. Statistics are especially important to draw general conclusions about a set of data from a sample. The numbers we see today are encouraging for the future of today’s patients and those who follow us. There is a reason for hope for all patients, but that too is a generalization.

For individual patients, and for me in particular, how well a specific drug worked on average for a group of patients studied in a particular location during a window of time is far from a perfect prediction of how well I’ll respond to the drug. How long the average myeloma patient diag­nosed in 2010 survived does not tell me whether I’m likely to to watch the 2022 World Cup or not. How well I do in treat­ment, how long I will survive, is controlled by too many factors, knowable and not, to make any reliable predictions.

During the post-game press conference fol­low­ing the last match of the regular season, the Sounder’s coach was asked if, given where the team was in June, he honestly believed his team would make the 2018 playoffs. He gave a wry smile and quickly responded yes because he knew the team had it in them to turn the season around and beat the odds. The people forecasting the Sounder’s final position in the league weren’t wrong, they just didn’t account for the many individual factors that influenced the out­come of the season.

The survival numbers and treat­ment reviews aren’t wrong as they relate to the myeloma pop­u­la­tion over­all, but they are much less relevant to any single patient. There are just so many factors that skew the numbers one way or the other. In some areas, I’ve already surpassed the averages for “patients like me.” In other respects, I’ve still to reach some longer mile­stones.

From my perspective, the lesson of the Sounders’ 2018 season is that for each individual person, none of the numbers really matter. I will do everything in my control to stay as healthy as possible. My care team will apply all methods possible to keep me healthy. I will get exactly as much time as all the factors taken together will deliver to me. Each day I’m here, though, I will sit back and enjoy the game.

UPDATE (November 9, 2018) – Unfortunately, the Sounders were elim­i­nated from the playoffs on November 8 by their hated rivals, the Portland Timbers. Just as they had during the regular season, the Sounders played to the very end, including thirty minutes of overtime and penalty kicks to break a tie. Objective observers are calling it one of the greatest MLS playoff matches ever. The Sounders entered the match with long odds of ad­vanc­ing, and through multiple dramatic lead changes met the challenge and pushed the opportunity to ad­vance to its limit.

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 Photo Credit: (c) 2013 Mark Pouley

Centurylink Field, home to the Seattle Sounders FC (and the Seattle Seahawks) is one of the most beautiful pitches in the MLS. On many days, like this one in 2014, the view is magical. During the last 10 years I’ve found refuge from a busy life in the stands, but since my diag­nosis, attending games has taken on a very special meaning and given me great joy.