Quick Answer. In some rare cases, excessive stress causes bleeding between periods. It is more common that another condition is responsible, such as pregnancy, polycystic ovary syndrome, infection, pelvic inflammatory disease or side effects of medication, according to WebMD.
Using the scientific method, you can repeat the experiment to find out for yourself whether or not the other researcher's assertions are true. This is a key factor that separates science from dogma! The other important part of scientific research is that a hypothesis must be falsifiable. A falsifiable hypothesis or theory is one where an experiment or another discovery can prove it to be wrong, untrue, and false.
Scientific principles are the foundation of scientific methods. In this book, youâll see how the principles reveal the big ideas behind our scientific discoveries and reflect the fundamental beliefs and wisdoms of scientists. The principles make the scientific methods coherent and constitute the source of creativity.