6 votes
Accepted

Are contraception effectiveness percentages per-user or per-use?

Neither. The percentages given are the percentage of couples using that method who will conceive over a year. So if 100 people use that 98% method, 2 will get pregnant each year. Here is a page ...
Kate Gregory's user avatar
  • 3,919
5 votes

How long is zinc sun block effective?

Zinc oxide is an inorganic compound with the formula ZnO. ZnO is a white powder that is insoluble in water and is widely used as an additive in numerous materials and products including rubbers, ...
Taylor's user avatar
  • 958
4 votes

Why is FMT an effective treatment for Clostridium difficile?

It seems to be unclear and likely some kind of combination of several factors. The paper Fecal microbiota transplantation in relapsing Clostridium difficile infection mentions two theories as to why ...
YviDe's user avatar
  • 6,992
4 votes
Accepted

Are retainers preferred to fiberotomies after dental work and, if so, why?

Retainers prevent the teeth from reverting to their original position, and therefore progressively force the periodontal ligament (PDL) to adapt itself to the new position. Doing a Fiberotomy ...
enap_mwf's user avatar
  • 1,225
4 votes
Accepted

What evidence does magnesium, zinc & melatonin help you sleep?

Magnesium, zinc and melatonin help to manage and control the sleep problems. These three natural components have their own mechanisms in managing the sleep disorders. Firstly, talking about Melatonin: ...
CCR's user avatar
  • 735
4 votes

Does brace to correct posture work?

Here's an paper that might help you: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3554027/ The short conclusion is "Application of the scapular brace improved shoulder posture and scapular ...
Kraken's user avatar
  • 141
4 votes
Accepted

Are antibiotics the only class of drugs whose effectiveness reduces over time?

This type of phenomenon will almost always be seen with drugs that target foreign pathogens capable of change, i.e., bacteria, viruses, fungi, parasites, etc. In addition to antibiotics, which target ...
Brian's user avatar
  • 144
3 votes

Why wouldn't the Pfizer, Moderna, AstraZeneca, and Johnson & Johnson vaccines be equally effective?

Even assuming the same ecological conditions, efficacy of a vaccine is in a (dose-dependent trade-off with side effects. (This was e.g. easily shown in the phase I/II trials of Moderna's vaccine.) ...
the gods from engineering's user avatar
3 votes
Accepted

Does reclining the front or back seat of a car reduce the effectiveness of the seat belt?

Yes. The effect of reclined seats on mortality in motor vehicle collisions. The reclined position is associated with increased occupant mortality in motor vehicle collisions. Why? flexion ...
Pobrecita's user avatar
  • 2,965
3 votes

How long is zinc sun block effective?

TL;DR: No, sunscreen needs to be re-applied every 2 hours Your product is the same as SPF 30 sunscreen SPF is a measure of how much solar energy (UV radiation) is required to produce sunburn on ...
Narusan's user avatar
  • 6,901
3 votes

What is the solution for Chikungunya?

Since 'the cure' or rather a vaccine against the virus is still only on the horizon, affected populations have to resort to prevention measures and supportive care, once the infection breaks out. Even ...
LаngLаngС's user avatar
  • 6,907
3 votes
Accepted

Is dental floss really effective? According to studies, it is not

Is dental floss really effective? The evidence shows that we don't know. Here the main issue is the lack of good evidence. How we find how effective is? Simple: we took a group of people with ...
sue's user avatar
  • 804
3 votes

Do computer glasses actually work?

No one likes CVS, and computer glasses are said to increase contrast and decrease glare to alleviate eye stress. If you are sure you will be using the computer in the future for prolonged periods and ...
nelomad's user avatar
  • 647
3 votes
Accepted

Verify/calculate VE from study data

This is a link to the full-test of the article whose results are presented in the post. https://www.acpjournals.org/doi/full/10.7326/M21-1577 The study reported used a study design called a “test ...
Diana Petitti's user avatar
3 votes

How would you properly interpret this graph?

On the Y-axis, you can see this is labeled as a cumulative incidence; cumulative means you're adding up over time. So, all the curves have to go up as you go to the right, because over time you ...
Bryan Krause's user avatar
  • 14.1k
2 votes
Accepted

Does drinking hot liquids help when you're sick?

Hot fluids(including water) can: Relieve Nasal Congestion Prevent Dehydration Soothe Uncomfortably inflamed membranes that line the nose and throat By relieving symptoms you can make a person feel ...
Pobrecita's user avatar
  • 2,965
2 votes

What diseases can ginseng supplement treat?

First, it is important to realize that there are two main types of ginseng in wide use: Asian ginseng and American ginseng. The Memorial Sloan Kettering Cancer Center has information on both types. ...
HDE 226868's user avatar
  • 1,848
2 votes

Is breathing into a paper bag an effective treatment for panic attacks?

Breathing into a paper bag to control hyperventilation might improve hypocarbia, but should NOT be done because of the risks of hypoxia and death. This case report shows that breathing into a paper ...
D.Tan's user avatar
  • 1,094
2 votes
Accepted

How long does it take for iron supplements to start improving energy levels? Is it instant or gradual?

Ferritin levels of 21 ug/L are on the extreme lower edge of the normal range. You can think about iron stores as follows. A healthy person will have iron stores of a few grams. Since iron is present ...
Count Iblis's user avatar
  • 2,270
2 votes
Accepted

Which has lower rate of getting pregnant and/or a venereal dicease in condom vs pill?

TL;DR The pill slightly more effective than condom for contraception. Other methods are better still. The pill is ineffective for preventing STI; condoms are mostly effective. In Full First things ...
bertieb's user avatar
  • 701
2 votes

Albuterol risks for long-term use

Albuterol is a short-duration ß2-receptor agonist (to which it owes its main effect, bronchodilation); and while it can produce some effect on ß1-receptors (producing effects such as tachycardia), ...
Gregorio Litenstein's user avatar
2 votes

Are fizzy "Effervescnt C" drinks any better than Vitamin C pills?

Effervescent pills have the advantage that since you ingest the active compount already dissolved the absorption rate is generally faster than for normal pills. This is useful when you need the drug ...
Variax's user avatar
  • 424
2 votes

What is the solution for Chikungunya?

The only effective management of viruses is by vaccination. In this way diseases such as measles have been eradicated from some countries. Currently there is no vaccine available so ecological ...
Graham Chiu's user avatar
  • 13.3k
2 votes

Does 'Sage Salvia officinalis' help reducing excessive hand sweating (palmar hyperidrosis)?

Salvia is a herbal treatment with a long tradition for this indication. sage leaves The HMPC has classified sage leaves as a traditional herbal medicinal product. ESCOP: internally for ...
LаngLаngС's user avatar
  • 6,907
2 votes
Accepted

Which one is better? Reading on a computer, on a tablet, or on paper?

To first establish a baseline: Reading is great for your brain, your mind, your intellect. But it can be bad for everything else. You sit, you concentrate, you stress your eyes. It is such a common ...
LаngLаngС's user avatar
  • 6,907
2 votes
Accepted

Efficacy and costs of medical treatments

Your analysis looks similar to: Incremental Cost-Effectiveness Ratio (ICER) which: ICER ... is used in cost-effectiveness analysis to summarise the cost-effectiveness of a health care intervention. ...
JMP's user avatar
  • 1,513
1 vote

What are the best natural foods to help reduce gynechomastia?

Foods that may reduce Gynocamastia: Livestrong: there's no association between any food and breast enlargement in men, and no special food you need to eat or avoid when you have the condition....
Pobrecita's user avatar
  • 2,965
1 vote

Do computer glasses actually work?

According to eye care providers, computer glasses designed for digital screens which can help alleviate many of the factors which cause eye strain symptoms, although do not completely prevent it. For ...
kenorb's user avatar
  • 4,705
1 vote

Which one is better? Reading on a computer, on a tablet, or on paper?

Reading on paper is way better from all perspectives. When you read on paper you are able to focus more and you are not putting pressure on your eyes and your brain passes the signals which help you ...
muzzi's user avatar
  • 139
1 vote

For Varicella zoster (chicken pox), when are vaccination/antiviral drugs effective?

According to the World Health Organization Administering the vaccine up to 3-5 days after exposure has been shown to reduce the severity of the disease significantly, but studies vary greatly as to ...
Mark's user avatar
  • 2,056

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