4 ms·

It's n = 800 which is way better than most studies, and it's a well designed study. Basic science research is way underfunded in essentially every country. Thi

It's n = 800 which is way better than most studies, and it's a well designed study. Basic science research is way underfunded in essentially every country. This is literally how the null hypothesis / statistical significance works; how is this crap science? If the measured effect is too tiny, you cannot conclude that it's a real effect.

btilly 5y ago
I agree that it is better than most studies, and that is part of the problem. The title as presented here is Lowering sodium intake doesn’t help heart patients. The impression that people will walk away from that title with is, "If you have heart problems, there is no need to eat a low sodium diet." This is not a hypothetical interpretation. I first saw this study at https://twitter.com/EricTopol/status/1510292643292491779 https://twitter.com/EricTopol/status/1510292643292491779, and that is exactly the impression that a well-known cardiologist drew. Many others came to the same conclusion. Now what should we expect? Their intervention reduced sodium consumption by 415 mg of sodium per day. (According to the least accurate method of measurement - self-reporting. The actual reduction was probably smaller.) If all else was equal, the correlation found at https://www.cdc.gov/salt/research_reviews/sodium_potassium_blood_pressure.htm https://www.cdc.gov/salt/research_reviews/sodium_potassium_b... we should expect that to reduce systolic blood pressure by 1.9 mmHg. However not all else is equal, these are all patients receiving medical care. If your blood pressure is too high, you receive more medication. So all else is not equal, and we should expect blood pressure to be approximately equal between the groups, and medication not. Therefore, to a first approximation, we should expect small differences in blood pressure, larger differences in required medication, and little difference in adverse events. They designed a study that did not report on average blood pressure between the groups, or what levels of medication were required, and would only notice a large difference in adverse events. And so they failed to find a result that they should not have expected to see, failed to look for the result that they should have expected, and it wound up being reported in a way that undermines public health messaging around sodium reduction. You may consider this quality scientific research. I don't.
- slothtrop 5y ago
  > The title as presented here is Lowering sodium intake doesn’t help heart patients. Yes, though this is the title posted to HackerNews, so I blame the poster. In the actual link, it's just : Reduction of dietary sodium to less than 100 mmol in heart failure (SODIUM-HF): an international, open-label, randomised, controlled trial

btilly 5y ago

I agree that it is better than most studies, and that is part of the problem. The title as presented here is Lowering sodium intake doesn’t help heart patients. The impression that people will walk away from that title with is, "If you have heart problems, there is no need to eat a low sodium diet." This is not a hypothetical interpretation. I first saw this study at https://twitter.com/EricTopol/status/1510292643292491779 https://twitter.com/EricTopol/status/1510292643292491779, and that is exactly the impression that a well-known cardiologist drew. Many others came to the same conclusion. Now what should we expect? Their intervention reduced sodium consumption by 415 mg of sodium per day. (According to the least accurate method of measurement - self-reporting. The actual reduction was probably smaller.) If all else was equal, the correlation found at https://www.cdc.gov/salt/research_reviews/sodium_potassium_blood_pressure.htm https://www.cdc.gov/salt/research_reviews/sodium_potassium_b... we should expect that to reduce systolic blood pressure by 1.9 mmHg. However not all else is equal, these are all patients receiving medical care. If your blood pressure is too high, you receive more medication. So all else is not equal, and we should expect blood pressure to be approximately equal between the groups, and medication not. Therefore, to a first approximation, we should expect small differences in blood pressure, larger differences in required medication, and little difference in adverse events. They designed a study that did not report on average blood pressure between the groups, or what levels of medication were required, and would only notice a large difference in adverse events. And so they failed to find a result that they should not have expected to see, failed to look for the result that they should have expected, and it wound up being reported in a way that undermines public health messaging around sodium reduction. You may consider this quality scientific research. I don't.

slothtrop 5y ago
> The title as presented here is Lowering sodium intake doesn’t help heart patients. Yes, though this is the title posted to HackerNews, so I blame the poster. In the actual link, it's just : Reduction of dietary sodium to less than 100 mmol in heart failure (SODIUM-HF): an international, open-label, randomised, controlled trial