Questions related to Medicine
The problem is in the second treatment group we had a higher value. In such cases what are the other applicable statistical methods to find the optimum level.
So, we usually leave the CaOH intracanal medicament for 14 days and then finish the final obturation. I am keen to know if this time-interval can be reduced by addition of Silver nanoparticles/TAP to CaOH, maybe reduce it from 14 days to 7 days or even 10 days?
Has there any research been done on this?
While I am crossing two paths, such as medicine and technology, I see that there are often barriers to understanding the two, but I want to know from the researchers who deal with both what challenges still exist.
Hi, I would like to know what is the type of study for the following research:
- The researcher conducted a descriptive study of medication errors in a hospital over 3 years. The number and characteristics of medication errors were the comparison sample.
- The researcher implemented a medication error mitigation program.
- Then the researcher studied the number and characteristics of medication errors in the 3 years before the implementation of the mitigation program. And these results were compared with the 3-year sample prior to implementation.
What is the type of study for this research?
Hello everyone! I am currently applying for postdoc positions, and I have been running into problems with finding a PI's faculty e-mail address. I am running this issue a lot when looking into PIs affiliated with their home university's school of medicine. For example, there are many PIs in the NYU Grossman School of Medicine who I would like to contact for possible positions, but I cannot find their e-mail addresses listed on their faculty page. The only contact information listed is a phone number for a specific treatment facility. (ex: "call this number to reach the cancer center")
Can someone please give me some advice? How can I find the corresponding e-mails for publications written by a PI's lab?
Is there any study showing that computer work causes increased eye pressure, a symptom representative of Glaucoma?
I have personally talked with several eye doctors, but they told me that it had not been proven so far. So, I am seeking such new researchers in this regard.
I would love to receive some recommendations from experts in regards to the topic, whether there are valid findings in research on biological markers for anxiety disorders. I am trying to gain some stable insight and be able to argue in favor of the notion, that no anxiety disorder "comes from a malfunction/sickness of the brain".
Thank you in advance!
I have a question or a discussion regarding human evolution in the future, if technology makes human being overcome limits of physiological stress as extreme temperatures , how evolutionary forces could shape our future ? as consequence , changes in human future lineage are not related with the distribution of the species . How traits are selected if we preserve most of the genetic pool trough Medicine , Technology , etc ?
SHARE RECOMMENDED READING PLEASE.
I am here for specific answers or a list of investigation tools to determine the newly developed drugs/inhibitors/medicines.
A patient with desminopathy survived Covid-19 six months ago without pneumonia, but with a temporary loss of smell and taste. After Covid-19, we note an accelerated progression of desminopathy, penetration accelerates, new muscles are quickly involved in the pathological process, muscle mass decreases, and heart function worsens. Perhaps the infection or its consequences are somehow connected with the mechanism of progression of desminopathy?
To save life in desminopathy, can the body purposefully reduce muscle mass, for example, due to decreased heart function or for another reason?
It is known that when hypothermia, the body sacrifices limbs for survival. Is it possible with desminopathy a similar phenomenon?
A patient with desminopathy (mutation Thr341Pro DES in a heterozygous state) with the progression of the disease has a decrease in taste and smell, immunosuppression, and an increase in IgA in the blood.
Oddly enough, but all this is characteristic of infections, including viral ones. For example, it is known that if the hepatitis C virus is not treated, then death will occur in 20 years.
In the identified case of late onset desminopathy, muscle weakness manifests itself at the age of 30, and death occurs 20 years after the onset of the disease.
Could the desmin mutation in myofibrillar myopathy be caused by an infection?
Perhaps the infection contributes to the progression of desminopathy?
Hello everyone, for my master thesis I investigate the acceptance of AI in medicine from patient side and therefore conduct a study. I would be thankful if someone of you would like to fill out the questionnaire, to help me out investigating this important topic. Thank you!
There are news on COVID-19 outbreak on ship, no matter cruise or military one.
And few aircraft carriers are also involved.
What is special about the ship arrangement that facilitated all these?
Nature 580, 18 (2020)
Limiting spread of COVID-19 from cruise ships - lessons to be learnt from Japan,
QJM: An International Journal of Medicine, , hcaa092,
COVID-19 outbreak on the Diamond Princess cruise ship: estimating the epidemic potential and effectiveness of public health countermeasures,
Journal of Travel Medicine, , taaa030,
Public Health Responses to COVID-19 Outbreaks on Cruise Ships — Worldwide, February–March 2020. MMWR Morb Mortal Wkly Rep 2020;69:347-352. DOI: http://dx.doi.org/10.15585/mmwr.mm6912e3
Estimating the asymptomatic proportion of coronavirus disease 2019 (COVID-19) cases on board the Diamond Princess cruise ship, Yokohama, Japan, 2020.
Euro Surveill. 2020;25(10):pii=2000180.
Chest CT Findings in Cases from the Cruise Ship “Diamond Princess” with Coronavirus Disease 2019 (COVID-19)
Complex systems are becoming one of very useful tools in the description of observed natural phenomena across all scientific disciplines. You are welcomed to share with us hot topics from your own area of research.
Nowadays, no one can encompass all scientific disciplines. Hence, it would be useful to all of us to know hot topics from various scientific fields.
Discussion about various methods and approaches applied to describe emergent behavior, self-organization, self-repair, multiscale phenomena, and other phenomena observed in complex systems are highly encouraged.
In my previous question I suggested using the Research Gate platform to launch large-scale spatio temporal comparative researches.
The following is the description of one of the problems of pressing importance for humanitarian and educational sectors.
For the last several decades there has been a gradual loss in quality of education on all its levels . We can observe that our universities are progressively turning into entertaining institutions, where students parties, musical and sport activities are valued higher than studying in a library or working on painstaking calculations.
In 1998 Vladimir Arnold (1937 – 2010), one of the greatest mathematicians of our times, in his article “Mathematical Innumeracy Scarier Than Inquisition Fires” (newspaper “Izvestia”, Moscow) stated that the power players didn’t need all the people to be able to think and analyze, only “cogs in machines,” serving their interests and business processes. He also wrote that American students didn’t know how to sum up simple fractions. Most of them sum up numerator and denominators of one simple fraction with the ones of the other, i.e. as they did it, 1/2+ 1/3 according to their understand is equal to 2/5 . Vladimir Arnold pointed out that with this kind of education, students can’t think, prove and reason – they are easy to turn into a crowd, to be easily manipulated by cunning politicians because they don’t usually understand causes and effects of political acts. I would add, for myself, that this process is quite understandable and expected because computers, internet and consumer society lifestyle (with its continuous rush for more and newer commodities we are induced to regard as a healthy behavior) have wiped off young people’s skills in elementary logic and eagerness to study hard. And this is exactly what the consumer economics and its bosses, the owners of international businesses and local magnates, need.
I recall a funny incident that happened in Kharkov (Ukraine). One Biology student was asked what “two squared” was. He answered that it was the number 2 inscribed into a square.
The level and the scale of education and intellectual decline described can be easily measured with the help of the Research Gate platform. It could be appropriate to test students’ logic abilities, instead of guess-the-answer tests which have taken over all the universities within the framework of Bologna Process which victorious march on the territories of former Soviet states. Many people can remember the fact that Soviet education system was one of the best in the world. I have therefore suggested the following tests:
1. In a Nikolai Bogdanov-Belsky (1868-1945) painting “Oral accounting at Rachinsky's People's school”(1895) one could see boys in a village school at a mental arithmetic lesson. Their teacher, Sergei Rachinsky (1833-1902), the school headmaster and also a professor at the Moscow University in the 1860s, offered the children the following exercise to do a mental calculation (http://commons.wikimedia.org/wiki/File:BogdanovBelsky_UstnySchet.jpg?uselang=ru):
(10 х 10 + 11 х 11 + 12 х 12 + 13 х 13 + 14 х 14) / 365 = ?
(there is no provision here on Research Gate to write square of the numbers,thats why I have writen through multiplication of the numbers )
19th century peasant children with basted shoes (“lapti”) were able to solve such task mentally. This year, in September, this very exercise was given to the senior high school pupils and the first year students of a university with major in Physics and Technology in Kyiv (the capital of Ukraine) and no one could solve it.
2. Exercise of a famous mathematician Johann Carl Friedrich Gauss (1777–1855): to calculate mentally the sum of the first one hundred positive integers:
1+2+3+4+…+100 = ?
3. Albrecht Dürer’s (1471-1528) magic square (http://en.wikipedia.org/wiki/Magic_square)
The German Renaissance painter was amazed by the mathematical properties of the magic square, which were described in Europe firstly in Spanish (the 1280s) and Italian (14th century) manuscripts. He used the image of the square as a detail for in his Melancholia I painting , which was drawn in 1514, and included the numbers 15 and 14 in his magic square:
16 3 2 13
5 10 11 8
9 6 7 12
4 15 14 1
Ask your students to find regularities in this magic square. In case this exercise seems hard, you can offer them Lo Shu (2200 BC) square, a simpler variant of magic square of the third order (minimal non-trivial case):
4 9 2
3 5 7
8 1 6
4. Summing up of simple fractions.
According to Vladimir Arnold’s popular articles, in the era of computers and Internet, this test becomes an absolute obstacle for more and more students all over the world. Any exercises of the following type will be appropriate at this part:
3/7 + 7/3 = ? and 5/6 + 7/15=?
I think these four tests will be enough. All of them are for logical skills, unlike the tests created under Bologna Process.
Dear colleagues, professors and teachers,
You can offer these tasks to the students at your colleges and universities and share the results here, at the Research Gate platform, so that we all can see the landscape of the wretchedness and misery resulted from neoliberal economics and globalization.
What is the best (or at least the most commonly used in medicine) way to put a Pearson's correlation coefficient into (strong, medium, weak) categories?
 strong (0.7 - 0.89), medium (0.5 - 0.69), weak (0.3 - 0.49)
 strong (0.6 - 0.79), medium (0.4 - 0.59), weak (0.2 - 0.39)
Casodex (or bicalutamide) is available only as a racemic mixture (S and R enatiomers): 1) the pharmacologically active R (-)-enantiomer, and 2) S-Casodex, the inactive (+) enantiomer. The S-enantiomer is thus the non-working compound but is also metabolized at a much lower rate. In other word, much higher plasma levels are the result. Does anybody know if casodex can increase emotional instability/anxiety? And which enantiomer is causing this?
With an increasing number of countries implementing digital health and digital public health tools, questions arise about whether these tools are effective and how to implement them best nationally. The lack of a validated and standard list of indicators complicates the comparison of digital health maturity between countries. We need guidance for governments in setting up strategies for the effective implementation and adoption of digital public health tools in routine care and the prevention of diseases.
To address this challenge, we want to invite researchers and practitioners from medicine, public health, economics, computer science, law, cultural studies, sociology, or other comparable disciplines. Participants should know about the development, implementation and evaluation of digital public health systems to take part in a Delphi study to choose the leading quality indicators to assess the maturity of national digital public health systems from four perspectives:
1. The information-telecommunication-technology requirements
2. The political support and legal regulation for the implementation and use of health technologies and the generated data
3. The application of concrete digital health tools to the national health system
4. The collective social willingness to use these tools
We are using a snowball approach to reach as many experts as possible. Please join our effort by participating in this Delphi study https://bit.ly/3raMsVY. Please forward this message to all your mailing lists of colleagues that might fit the purpose of this study. Every participation will be greatly appreciated and contribute to a better understanding of international digital public health systems.
This Delphi study will be conducted within the German Leibniz ScienceCampus Digital Public Health research project entitled "Developing a Maturity Measurement Model for Digital Public Health: The Digital Public Health Readiness Index".
Best regards and take care,
(on behalf of the digital public health readiness index team and the EUPHA Digital Health Section)
Link to Survey: https://bit.ly/3raMsVY
I submitted my manuscript to one of the Lancet Journals. The status remained as “submitted to Journal” till mid February.After that it changed to “Decision in Process”. The status has remained so till April. I have also written to the journal thrice but did not receive any reply from them. I am very confused about the status of my manuscript. There seems to be no option to retract the manuscript too. My mentor is not allowing me to contact the Ombudsman.
I have previously submitted manuscripts twice to Lancet journals but they Would make an editorial decision within 3 days.
Is the current case just a technical glitch or are they pondering over my manuscript? What are the chances of a positive response from the journal based on my case? Also how do I go about the situation?
I want to find some medicines which have the neuroprotection effects, as i hope that it has been researched in other diseases but not the field i am researching now. I know maybe i could find the suitable medicine if i have read many related papers, but is there another way to find it? Thanks.
A plant-based diet is a diet based on fruits, vegetables, whole grains, and legumes while a vegan diet is strictly against all animal products. Whats your openion about PBD and vegan and their effects on our health?
I am working on my MSc dissertation, investigating breast protection bras for female boxers. I am looking at their protection but also the fit and shaping of them and how this relates to their comfort during wear. Is there any sort of classification of the shape of women's breasts? How would I describe the natural breast shape?
The recent changes in the COVID-19 epidemic have led to the emergence of a new SARS-CoV-2 Variant of Concern (VOC), named "Omicron," and the number of Omicron cases were consistently increasing around the world. The health professional's knowledge is of utmost importance to prevent and control the spreading of the SARS-CoV-2 Omicron Variant of COVID-19. In this regard, we would likely to know the level of knowledge and Perceptions of health professionals about the SARS-CoV-2 Omicron Variant; this can provide a greater opportunity to understand the existing knowledge gaps about the novel Omicron variant and to scale up the interventional strategies. Thus, I invite you to participate in this short survey and provide your
valuable opinion regarding the SARS-CoV-2 Omicron variant.
Thanking you in advance
What is the extent of bias risk between standard and autobiographical case reports in medicine and is there any medical journal (indexed or not indexed in MEDLINE) publishing or having a history of publishing autobiographical case reports?
In the structure of many drugs, there is a carboxylic group
What is the significance of this group? Why should it exist in the structure of a drug?
Do you know any article or book or reference about this subject?
Thanks a lot
COVID-19 is mainly a respiratory disease that affects the lung, although other organ structures with endothelium seems to be affected too.
When should we do imaging?
What is the aim of the imaging?
How can it help with management?
Do you agree with the following consensus statement?
How will you adjust your own practice and difficulties encountered? Why?
The Role of Chest Imaging in Patient Management during the COVID-19 Pandemic: A Multinational Consensus Statement from the Fleischner Society. Chest. 2020 Apr 07.
What types of exercises and training variables (volume, intensity, repetitions, frequency, exercise selection, exercise order, and rest) are recommended for patients with Multiple sclerosis (MS)?
COVID-19 is changing the social life of all people. Jumping out of the personal aspect, how does it affect the family as a whole.
Family is regarded as the fundamental structure of the society, will COVID-19 changes the future family structure, unit and model?
How is it affecting gender issues too?
Besides, why is domestic violence increasing? Is psychology and psychiatry playing a role?
 Campbell AM. An increasing risk of family violence during the Covid-19 pandemic: Strengthening community collaborations to save lives.
Forensic Science International: Reports vol. 2 (2020): 100089.
COVID-19: Reducing the risk of infection might increase the risk of intimate partner violence
The pandemic paradox: The consequences of COVID‐19 on domestic violence
J Clin Nurs
To be a better medicine what will we consider as chemically potential?? in terms of Chemical Reactivity of Targeted Drug Molecules with other potential molecules
Artificial intelligence is being used more and more in all medical fields. What do you think will be the development directions for the next 5 years?
Expanded Disability Status Scale (EDSS) is a method of quantifying disability in multiple sclerosis that is the most widely used measurement tool to describe disease progression in patients with MS.
I have received the following polite email request from Medical Research Archives, European Society of Medicine a number of times.
Is it legitimate? Would you mind sharing your thoughts if you have any experience of this kind? Thanks
Dear Dr. Yegnanew A. Shiferaw,
If you have a few minutes I wanted to discuss your COVID-19 research. I am serving as the editor of a special theme issue on Advancements in COVID-19 which will be released by the European Society of Medicine next year and I was thinking that something related to your work on "Regime shifts in the COVID-19 case fatality rate dynamics: A Markov-switching autoregressive model analysis" would be interesting to include in the issue. Perhaps you could tell me more about your research in this area.
This could be in the form of a research article or even a review article.
Might this be a possibility?
L. Smith, M.D.
Medical Research Archives
European Society of Medicine
Online ISSN: 2375-1924
Print ISSN: 2375-1916
PubMed ID: 101668511
If I have an experience but no certificate in Machine Learning, and have both experience and certifcate in Medicine (Urology) ... and want to publish a peper that include an interaction between these 2 feilds, in either Urology or CS journals. Should i add a coauthor who is certified in Data science or CS? ... if not, Would it be necessary to prove my competency in ML by any means?
What types of exercise and training variables (volume, intensity, repetitions, frequency, exercise selection, exercise order, and rest) are recommended for patients with Multiple sclerosis (MS)?
I hope you had a wonderful Christmas. Im very much interested in teaching and I would like to ask your views on a highly ( to me at least) interesting topic. There are probably as many methods of teaching methods as there are lecturers but here are a few types accepted in literature.
- Student-Centered / Constructivist Approach.
- Inquiry-Based Learning.
- Flipped Classroom.
- Cooperative Learning.
- Personalised Education.
Which one do you use and why?
Best wishes Henrik
In a patient with hereditary desminopathy (mutation Thr341Pro DES in the heterozygous state) over the past three years, an increase in the blood uric acid level up to 440-480 µmol / l was established by 1.5 times (the norm is 428.4 µmol / l). With the progression of the disease, the level has risen and is above normal. It is known that uric acid is an antioxidant. Is it necessary to reduce the level of uric acid? The patient has no problems with the joints.
TB is transmitted through the air. The droplet nuclei generated when a sputum positive pulmonary TB patients coughs, mixes in the air and are carried to a susceptible person in the vicinity or by air currents to longer distances. Sputum Negative TB patients may also contribute in transmission of infection to a smaller extent. Now my concern is that, "Can housefly provides an additional epidemiological link to spread TB infection in the community?"
Metabolic rewiring and epigenetic remodeling, which are closely linked and reciprocally regulate each other, are among the well-known cancer hallmarks. Studies have reported use of Onco-metabolites to metabolically reprogram the epigenetic of cancer. I was wondering what might be major limitations of such techniques?
Jufa is a European native plant and being used in Ayurveda and Unani system of medicine since long. It's one of the ingredients of Gojivhadi kashyam and Jufex of Aimil Pharma.
Have you ever imagined how the physically disabled people feel under COVID-19?
Which type of disability is most impacting these minority under COVID-19?
Autism? Cleft patients? Mental health patients? Deaf? Dumb? Blind? Loss of limbs?
How can we help them?
I am thinking about adapting neuroscience tools for identifying the patient’s reactions in making the diagnosis. I know there is a debate, but I cannot find any literature. Could anyone help me?
Hello, good day.
Please I'm working on a project which needs a "review of relevant theories" of the study "medical negligence behavior"
I found 2 theories relating to this study (conflict theory and theory of negligence), but they are not enough.
Please can I get more theories concerning medical negligence?
I started my studies on histology and I realized most of well established text-books don't use scale bars in their images, except the books of the American-German Thieme Publishing Group. I think it is a lack of technical rigorosity, even though most of books treat the issue only on a qualitative point of view. So, what do you think about that? Should the publishers in that area change their concept to increase their accuracy?
Vertigo is a condition that can make it feel like you or your surroundings are spinning, sometimes leading to a loss of balance, according to the U.S. National Library of Medicine.
Coronavirus 2019 or COVID-19 is a novel entity which had led to many challenges among physicians due to its rapidly evolving nature. Vertigo or dizziness has recently been described as a clinical manifestation of COVID-19.
So, Are dizziness and vertigo COVID-19 Symptoms? and why?
Applications of bioinformatics in medicine is a key factor in technological advancement in the field of modern medical technologies.
In which areas of medical technology are the technological achievements of bioinformatics used?
What are the applications of bioinformatics in medicine?
I invite you to the discussion
Thank you very much
Reality may increasingly hurt – #Genomic #targetedtherapy
Changes between 2006 and 2020
-eligibility from 5.13% to 13.60% *only*
-response from 2.73% to 7.04% *only*
The authors use in their discussion different paraphrasing: “the percentage of eligibility for and response to genome-targeted drugs increased 54% and 28%, respectively”
which from the objective point of view is correct, but this implies a major improvement, although the reality of inefficiency is different
Some may state *the house of cards collapse of the breakthrough* ?
Otherwise today's basics of biotechnological power politics in created hypes of landmarks, breakthroughs, which might be seen in the accordance of the Latin epic poem, The Aeneid by Virgil:
‘parcere subiectis, et debellare superbos’ (I believe it at any rate)
Article Haslam et al. (2021) Ann Oncol 2021, DOI 10.1016/j.annonc.2021.04.003
The Aenedid from Virgil Vergil (19 BC), Aeneis, Liber sextus, Vers 847-853.
#medicine #health #medicalsciences #breakthroughs #landmarks #hallmark #hype #criticalthinking
Under COVID-19, healthcare facilities requests a lot of sterilization to prevent hospital transmission of the disease. Bleach solution and many other disinfection agents may not be effective against such a large scale of usage.
Can ultraviolet light be used to inactivate the virus?
Can it be applied on whole room disinfection?
Can it be used on high turnover medical equipment sterilization? E.g. stethoscope.
Can it be used to inactivate infected donors' blood products or body fluids?
It's 99 days since the first case of COVID-19 in Hong Kong, and we are welcoming the 5th days of 0 new cases of COVID-19 following a week of <10 cases per day.
How should we define the end of a local endemic?
How long should the latent period be defined?
When is it safe to resume social activities?
Should territory wide screening of asymptomatic people be done before declaring the end of endemic?
We are compiling comprehensive details for traditional medicines and their marketing approval in a particular country. For now, we are reviewing Kampo Medicines of Japan. But somehow we are not able to get suitable guideline documents (original from Japanese Regulatory Agency's Website). Can anyone guide us? From where we can find guidelines for marketing approval of Kampo medicine in Japan?
How can you decide the judgment on a specific article whether it is good or not, is your judgment depends on the title of the article or the abstract or the publishing journal or something else?
Please, share us your opinions about the discussion
I have watched a child crying loudly in pain, while collecting blood for testing. Can we develop a technique which can collect the blood or inject a medicine to children in a complete pain-free way ?
Iam a dental student and i want to increase my knowledge in writing drug chart to patient in the future, can you give me some advises to increase my knowledge in this field, i the name of drug and the number of dose is very consued and i forgot it fast so how the doctors write it easy...... So can you advise me to be good in the future
Hello, I will try to produce Sb2S3 films with thermal evaporation technique using Sb2S3 pellets or Sb pieces. Then I will complete the production with thermal annealing. Could you please give information about the risks of Sb2S3 pellets or Sb pieces and the precautions I should take?
Under the pandemic of COVID-19, screening becomes important to tackle the spread. Fever is one of the screening criteria for many public places screening for access.
However, how is fever defined?
Is the 0.1 degree change makes the significance?
What is the range of standard deviation being acceptable?
What machine is accurate?
Is those hand held infrared measuring machines reliable?
Is there scenarios giving false negative tha may make a huge consequence?
Normal Body Temperature: A Systematic Review.
Open Forum Infect Dis. 2019;6(4):ofz032. Published 2019 Apr 9.
I know that an infant's brain can repair itself when damaged but why doesn't the same happen in adults after stroke or brain injuries?
With the developing stories of the spread of COVID-19 all around the world, which has been declared as a pandemic by WHO recently, I am wondering, in how much time this virus would vanish from the surface of the Earth? Is there any scientific study available for this?
Please share your opinions.
The development of a vaccine for COVID-19 has become a battleground for many countries to prove to the world/their own peoples that their technology is superior and better than the competitors at the international stage. it is always a point of concern when science is serving the political establishment. Russia claimed that they have developed 'the first' Covid-19 vaccine. WHO is raising concern about the validity of this claim and urging Russia to provide sufficient data to back this claim.
Is it possible for the same scenario to be repeated in the US? An election is near and COVID-19 vaccine development can influence the result.
Dear seniors and researchers,
Briefly introducing myself, I am a fourth year medical student from Indonesia. Currently, I am performing a multiple logistic regression on several possible factors affecting medical student preference toward distance learning in this pandemic era. Honestly, it is my first time in using logistic regression in my work, and I might encounter several confusing issues regarding this statistical procedure. I have selected 14 eligible covariates for multiple logistic regression according to its significant p-value (0.000) during their simple logistic regression. After including all of those 14 covariates to the model, the ExpB (odds ratio) of all 14 covariates become insignificant despite decent model (Good result of Omnibus test, R-squared, and Holmer and Lemeshow test). All of statistical procedure were performed in SPSS ver 22.
Regarding this issue, what should I do in responding those finding? Is it correct to interpret that there were no significant relationship between all of 14 covariates and dependent variable (student preference toward distance learning) simultaneously? Or is there any suggestion of appropriate technical steps in conducting multiple regression analysis?