1 00:00:09,075 --> 00:00:11,778 So, a few more things about study designs. 2 00:00:11,778 --> 00:00:15,815 Your number one question is how good is your primary research question? 3 00:00:15,815 --> 00:00:20,420 At the end of the day, when your research is done, and your data 4 00:00:20,653 --> 00:00:25,592 analyzed, will the answer -- regardless of what the answer is to the primary research 5 00:00:25,592 --> 00:00:27,927 question, advance scientific knowledge or clinical practice? 6 00:00:27,927 --> 00:00:33,333 If it does not advance scientific knowledge or clinical practice, if it does not at least 7 00:00:33,333 --> 00:00:37,370 lay the necessary foundation that's missing to advance it, you have failed, 8 00:00:37,370 --> 00:00:40,407 and you don't have a good primary research question. 9 00:00:42,008 --> 00:00:44,644 I'm not saying that you answered 10 00:00:44,644 --> 00:00:49,015 the question the way you hoped it would be answered. 11 00:00:49,015 --> 00:00:52,485 But you know, does a failed -- like, 12 00:00:52,485 --> 00:00:57,724 if you get the exact opposite answer, does that still advance science? 13 00:00:57,724 --> 00:00:59,492 It's an important thing. 14 00:00:59,492 --> 00:01:02,095 If you get a negative result, 15 00:01:02,095 --> 00:01:06,900 not that positive result you're hoping for, that's still important. 16 00:01:06,900 --> 00:01:11,704 The second most important element is a good primary outcome 17 00:01:11,704 --> 00:01:14,340 measure that's clinically meaningful and simple. 18 00:01:15,575 --> 00:01:19,312 I now have to write and turn these endpoints for studies 19 00:01:19,312 --> 00:01:24,084 into labels that the American public can read and that the prescribers can understand. 20 00:01:24,084 --> 00:01:27,487 It is really hard to interpret some of these endpoints. 21 00:01:27,487 --> 00:01:28,488 It makes sense 22 00:01:28,488 --> 00:01:33,259 when you're trying to cover all your ground to combine all this stuff together, 23 00:01:33,259 --> 00:01:38,031 but as you get into the discussions of measures and endpoints in this course, 24 00:01:38,031 --> 00:01:42,769 you'll realize it can be very hard to actually express it and explain it 25 00:01:42,769 --> 00:01:43,803 to somebody. 26 00:01:43,803 --> 00:01:49,576 But I want to give a little bit more information about how you want to start 27 00:01:49,576 --> 00:01:52,979 designing one of these lovely studies we're just talking about. 28 00:01:54,047 --> 00:01:58,318 You've got study aims, your background, your rational, then you're going to talk 29 00:01:58,318 --> 00:02:00,954 about the endpoints, the outcome variables, any assessment 30 00:02:00,954 --> 00:02:04,557 you're going to take on the people in your clinical trial, 31 00:02:04,557 --> 00:02:07,861 or the animals in your trial, whatever's in the trial. 32 00:02:07,861 --> 00:02:09,829 What are your assessments? Be specific. 33 00:02:09,829 --> 00:02:12,132 Don't tell me you're measuring sleep, folks. 34 00:02:12,132 --> 00:02:14,734 Tell me exactly how you are measuring it. 35 00:02:15,835 --> 00:02:18,438 Talk about -- think about the specific elements. 36 00:02:18,438 --> 00:02:20,039 Is it sensitive to change? 37 00:02:20,039 --> 00:02:23,943 Do not take a wooden ruler and try to measure my waistline. 38 00:02:23,943 --> 00:02:27,180 That is not a good way to take that measurement. 39 00:02:27,180 --> 00:02:30,416 You want something that's reliable. You want something that's valid. 40 00:02:30,416 --> 00:02:34,921 You need to know all this information about those measures you're going to use 41 00:02:34,921 --> 00:02:37,190 because the measures are what you're going 42 00:02:37,190 --> 00:02:40,760 to use in some combination to get that actual final endpoint. 43 00:02:41,794 --> 00:02:43,163 Think about your inclusion/exclusion criteria. 44 00:02:43,163 --> 00:02:46,733 Can you measure all of these things on the people in your study? 45 00:02:46,733 --> 00:02:51,404 We'll talk a lot about this, and Wendy Weber will talk a little bit more about it 46 00:02:51,404 --> 00:02:53,039 when she talks about protocols, too. 47 00:02:53,039 --> 00:02:56,876 So you have to make sure people are legal to be in your study. 48 00:02:56,876 --> 00:02:59,078 But sometimes I see so many exclusion criteria, 49 00:02:59,078 --> 00:03:02,882 I'm like there's nobody left in this world that can be in your study. 50 00:03:03,983 --> 00:03:07,053 So you've got to balance and think about safety. 51 00:03:07,053 --> 00:03:10,823 Like, you know, can they not ethically be in your trial? 52 00:03:10,823 --> 00:03:14,794 And after that, you might want to let everybody else in. 53 00:03:14,794 --> 00:03:18,331 How do you start designing? Think about that accrual plan. 54 00:03:18,331 --> 00:03:20,033 Think about the preparatory test. 55 00:03:20,033 --> 00:03:24,137 What's the timeline for your overall study and for the individual participants? 56 00:03:24,137 --> 00:03:26,873 Do they have to come between 9:00 a.m. 57 00:03:26,873 --> 00:03:27,907 and 4:00 p.m. 58 00:03:27,907 --> 00:03:30,643 on days that they are likely to work? 59 00:03:31,344 --> 00:03:33,613 That is going to make a big problem. 60 00:03:33,613 --> 00:03:38,151 Yeah, someone's like raising their head and I'm like, yeah, that's right, it's a problem. 61 00:03:38,151 --> 00:03:40,153 Treatments. What are the participant implications? 62 00:03:40,153 --> 00:03:43,556 So I was in a trial, and I couldn't take certain antibiotics. 63 00:03:43,556 --> 00:03:46,960 So then, of course, I get sick and I need an antibiotic. 64 00:03:46,960 --> 00:03:50,964 So there was this back and forth about what drug I could actually take. 65 00:03:52,065 --> 00:03:56,069 But you have to think about the implications on your participants. 66 00:03:56,069 --> 00:03:57,870 What is the exact product? 67 00:03:57,870 --> 00:04:01,140 What is the exact dose? What about the quality? 68 00:04:01,140 --> 00:04:04,444 How is it administered? Can you reproduce the intervention? 69 00:04:04,444 --> 00:04:10,250 Whether it is a drug or whether it is yoga, can you actually reproduce that intervention? 70 00:04:12,919 --> 00:04:17,223 So if I say yoga, exactly what type of yoga is it? 71 00:04:17,223 --> 00:04:19,759 Am I doing it once a week? 72 00:04:19,759 --> 00:04:22,262 Six times a week? What's going on? 73 00:04:22,262 --> 00:04:24,430 Does it interfere with patient management? 74 00:04:24,430 --> 00:04:25,865 Again, kind of my 75 00:04:25,865 --> 00:04:31,271 being in that trial interfered with my doctor trying to give me a medication. 76 00:04:31,271 --> 00:04:34,841 Generalizability is often lost in this quest for specificity. 77 00:04:34,841 --> 00:04:37,377 So you have to decide and balance. 78 00:04:37,377 --> 00:04:42,815 And at different parts of your scientific knowledge, you may decide to have more 79 00:04:42,815 --> 00:04:43,950 or less generalizability. 80 00:04:43,950 --> 00:04:44,350 Specify 81 00:04:44,350 --> 00:04:49,322 the criteria for withdrawal from studies or a deviation from the protocol definitions. 82 00:04:49,322 --> 00:04:54,294 If they do not show up at exactly day 72, does it matter? 83 00:04:54,294 --> 00:04:58,131 Or is it day 72 plus or minus seven days. 84 00:04:58,131 --> 00:05:01,200 Like, what are the windows for every assessment? 85 00:05:01,200 --> 00:05:07,340 Sometimes you have to be super precise and sometimes you can be a little bit looser. 86 00:05:08,841 --> 00:05:10,343 Sometimes someone may need 87 00:05:10,343 --> 00:05:15,181 to go off intervention, but they do not need to leave your study. 88 00:05:15,181 --> 00:05:18,518 You can still follow them and take the assessments. 89 00:05:18,518 --> 00:05:22,989 You want to have a list of all the concurrent medications, procedures, 90 00:05:22,989 --> 00:05:27,827 et cetera, that are prohibited, permitted, and how you're going to record them. 91 00:05:27,827 --> 00:05:30,430 Do remember, it's not just medicine, folks. 92 00:05:30,430 --> 00:05:32,298 These people are drinking teas, 93 00:05:32,298 --> 00:05:35,668 they are taking supplements, they are taking over-the-counter medications. 94 00:05:36,102 --> 00:05:41,741 Do you want them to still do Tai chi or go to spinning class if you are studying yoga? 95 00:05:41,741 --> 00:05:45,611 You need to think about all the different things they could be doing 96 00:05:45,611 --> 00:05:47,680 that might interfere with what you're studying. 97 00:05:47,680 --> 00:05:50,650 But also, you have to think about, you know what, 98 00:05:50,650 --> 00:05:54,787 sometimes people are going to get headaches and what are they going to take? 99 00:05:54,821 --> 00:05:57,724 Like, don't tell them to disavow or not do anything 100 00:05:57,724 --> 00:06:02,829 because you'll get nobody in your study, or they'll do it anyway and just not tell you. 101 00:06:02,829 --> 00:06:04,430 So what is the dose? 102 00:06:04,430 --> 00:06:07,633 It might be the number of sessions, or pills, or treatments. 103 00:06:07,633 --> 00:06:09,369 It could be social media attempts. 104 00:06:09,369 --> 00:06:14,107 So if some of these studies are in fact trying to actually tell you, like, 105 00:06:14,107 --> 00:06:17,810 all right, we want to give you information about your cigarette smoking. 106 00:06:17,810 --> 00:06:20,880 Well, do I give you one text message a day? 107 00:06:20,880 --> 00:06:23,649 So I send you six text messages a day 108 00:06:23,649 --> 00:06:28,855 to try to keep you so that you are still -- you have not started smoking again? 109 00:06:28,855 --> 00:06:30,256 What is the amount? 110 00:06:30,256 --> 00:06:30,690 Frequency. 111 00:06:30,690 --> 00:06:33,459 Do I go to the chiropractor once a week? 112 00:06:33,459 --> 00:06:34,927 Seven days a week? 113 00:06:34,927 --> 00:06:37,797 How frequently do I go? And for how many weeks? 114 00:06:37,797 --> 00:06:39,232 And for how much time? 115 00:06:39,232 --> 00:06:42,402 There was one good massage study that they looked at 30-minute, 116 00:06:42,402 --> 00:06:45,838 60 minute, or 90-minute massage. Once, twice, or three times a week. 117 00:06:45,838 --> 00:06:48,408 Now they did take out something because they're like, 118 00:06:48,408 --> 00:06:51,844 well, you're not going to study three times a week, 90-minute massage. 119 00:06:51,911 --> 00:06:54,180 People will not go to that. 120 00:06:54,180 --> 00:06:56,416 But there've been these very interesting 121 00:06:56,416 --> 00:07:00,953 dosing studies, not just of drugs, but a lot of other interventions. 122 00:07:00,953 --> 00:07:05,091 Same thing if you're talking about a lot of psychological interventions. 123 00:07:05,091 --> 00:07:06,225 How much practice? 124 00:07:06,225 --> 00:07:09,962 What do people need to do outside of a classroom? 125 00:07:09,962 --> 00:07:11,497 Who is the leader? 126 00:07:11,497 --> 00:07:14,500 Who is the surgeon? Who is that person? 127 00:07:14,500 --> 00:07:18,070 How much contact is there and how well trained are they? 128 00:07:18,070 --> 00:07:19,705 There're a lot of combinations. 129 00:07:19,705 --> 00:07:21,674 You're only going to be able 130 00:07:21,674 --> 00:07:26,379 to test some of these possible doses, but it's important to look at it. 131 00:07:26,379 --> 00:07:31,417 As I mentioned at the very end, you've got to think about your practitioner impact. 132 00:07:31,417 --> 00:07:34,353 There could be a lot of false/negatives and false/positives 133 00:07:34,353 --> 00:07:39,225 that come up here because we have some people that are just -- they're enigmatic. 134 00:07:39,225 --> 00:07:41,494 People like them and good things happen. 135 00:07:42,628 --> 00:07:46,966 But sometimes you say, listen, I'm doing a proof of principle study. 136 00:07:46,966 --> 00:07:51,671 If the best massage therapist, who's really well-trained, and trains others, if that 137 00:07:51,671 --> 00:07:57,076 person cannot give a massage that improves low back pain, probably nobody can do it. 138 00:07:57,076 --> 00:08:02,515 If my best surgeon cannot fix this, maybe nobody can be trained to do that. 139 00:08:02,515 --> 00:08:05,384 So sometimes we actually go for really well-trained 140 00:08:05,384 --> 00:08:09,722 folks in a proof of concept model and then broaden that out. 141 00:08:10,022 --> 00:08:12,525 But again, you probably want to choose techniques 142 00:08:12,525 --> 00:08:15,628 that can be generalized if you're going to do that. 143 00:08:15,628 --> 00:08:19,732 But other times, such as the Perlman studies that were looking at massage 144 00:08:19,732 --> 00:08:23,803 actually for osteoarthritis of the knee, he chose Swedish massage because he said 145 00:08:23,803 --> 00:08:28,474 that's what everybody is trained in in most of the countries he was looking at. 146 00:08:28,474 --> 00:08:33,713 He was like, that's the foundation that they have, we want to build on that. 147 00:08:33,713 --> 00:08:35,748 So the study analysis population. 148 00:08:35,748 --> 00:08:38,150 You have this mechanistic proof of concept. 149 00:08:38,150 --> 00:08:40,887 That's your throw in the best at it. 150 00:08:40,887 --> 00:08:41,888 We sometimes call 151 00:08:41,888 --> 00:08:47,360 these also the protocol analyses that we do because we only use the patients that behave, 152 00:08:47,360 --> 00:08:51,797 the study subjects who do everything we tell them, we'll analyze them here. 153 00:08:51,797 --> 00:08:56,602 That's along the idea of, like, in the perfect world what might we expect? 154 00:08:57,770 --> 00:09:00,706 But general use is like these intent-to-treat analyses. 155 00:09:00,706 --> 00:09:01,440 That's everybody. 156 00:09:01,440 --> 00:09:06,212 You tell a patient to take a drug, they don't necessarily take it. 157 00:09:06,212 --> 00:09:10,616 You randomize a patient to a study arm; they don't necessarily comply 158 00:09:10,616 --> 00:09:11,717 with your intervention. 159 00:09:11,717 --> 00:09:15,755 So intent to treat versus kind of these different completers analyses, 160 00:09:15,755 --> 00:09:19,425 this gets down to what is your data analyses population. 161 00:09:20,092 --> 00:09:24,730 So we could say ITT, or intent to treat, once randomized, always analyzed. 162 00:09:24,730 --> 00:09:26,165 And then observational trial, 163 00:09:26,165 --> 00:09:31,170 we're like, once you're in the trial, we follow you in the trial. 164 00:09:31,170 --> 00:09:35,808 You assume that all study participants are adhering to your study regiment 165 00:09:35,808 --> 00:09:37,944 and that they complete the study. 166 00:09:37,944 --> 00:09:42,949 So they -- you assume they behaved perfectly, regardless of what they actually do. 167 00:09:44,550 --> 00:09:48,721 Most of your regulatory agencies are going to say, "We 168 00:09:48,721 --> 00:09:52,858 expect you to do an intent-to-treat analysis." Most high-quality research 169 00:09:52,858 --> 00:09:57,396 regulated or not, we assume you should be doing intent-to-treat analysis. 170 00:09:57,396 --> 00:10:01,534 But then people kind of want to skirt the edges. 171 00:10:01,534 --> 00:10:05,271 They do something called a modified or MITT analysis. 172 00:10:05,271 --> 00:10:06,939 Modified intent to treat. 173 00:10:06,939 --> 00:10:11,911 They may only include patients who start the intervention they're assigned to. 174 00:10:11,911 --> 00:10:16,048 So they include the study subjects who start the intervention. 175 00:10:17,149 --> 00:10:17,483 Well, 176 00:10:17,483 --> 00:10:22,855 if I randomized you to go to psychotherapy versus not, you decide you don't like what 177 00:10:22,855 --> 00:10:27,560 your randomized to, and you don't start, you know, that's still telling me something. 178 00:10:27,560 --> 00:10:31,263 So should I really throw those people out of my analyses? 179 00:10:31,263 --> 00:10:34,266 It depends on the question you're trying to answer. 180 00:10:34,266 --> 00:10:39,305 Sometimes people say if they don't make it to like the first or the second 181 00:10:39,305 --> 00:10:41,641 post-baseline assessment, then I don't count them. 182 00:10:41,707 --> 00:10:46,512 I'm like, well, again, you can't really compare both groups of patients then. 183 00:10:46,512 --> 00:10:50,182 You know, your study subjects may no longer be comparable. 184 00:10:50,182 --> 00:10:52,018 You have undermined the randomization. 185 00:10:52,018 --> 00:10:55,688 So that's the problem with modified intent to treat analyses. 186 00:10:55,688 --> 00:10:58,658 You've got to be very careful with those. 187 00:10:58,658 --> 00:11:02,695 But sometimes we do these completers or adheres analyses that, again, 188 00:11:02,695 --> 00:11:06,732 you're only dealing with your well-behaved and that's a problem. 189 00:11:06,732 --> 00:11:12,271 So as John described last night, we have this kind of superiority in equivalence. 190 00:11:12,638 --> 00:11:16,042 So I wanted to put this in a picture for you. 191 00:11:16,042 --> 00:11:20,079 Equivalence or no difference, the confidence in a role that we'll talk about 192 00:11:20,079 --> 00:11:22,248 in a hypothesis testing lecture, everything's inside 193 00:11:22,248 --> 00:11:25,051 this little, tiny, round, kind of in the middle. 194 00:11:25,051 --> 00:11:27,186 It's like where there is no difference. 195 00:11:27,186 --> 00:11:29,355 So this is a normal distribution curve. 196 00:11:29,355 --> 00:11:32,792 And this line in the middle is kind of the zero. 197 00:11:33,693 --> 00:11:37,463 It's the middle of the bell curve or the Gaussian curve. 198 00:11:37,463 --> 00:11:42,234 So if you're in a little tight area here, there's no difference between your study 199 00:11:42,868 --> 00:11:42,902 arms. 200 00:11:42,902 --> 00:11:46,972 If you're in these orange areas in either end, you have superiority. 201 00:11:46,972 --> 00:11:52,445 So when I test two arms, I can come up with a value along this curve. 202 00:11:52,445 --> 00:11:56,849 And if I'm far enough out, that's saying that basically these two groups 203 00:11:56,849 --> 00:11:58,250 are statistically different, 204 00:11:58,250 --> 00:12:01,420 And it's probably not just a random error that I'm saying that that 205 00:12:02,521 --> 00:12:05,091 noninferiority 206 00:12:05,091 --> 00:12:08,160 is when I say, well, they may be a little bit inferior 207 00:12:08,794 --> 00:12:09,595 or they could and it's probably not just a random error that I'm [unintelligible]. 208 00:12:09,595 --> 00:12:09,895 Non-inferiority is when I say, well, they may be a little bit inferior, 209 00:12:09,895 --> 00:12:10,196 or they could even be superior, so it kind of gives me this huge area to be in. 210 00:12:10,196 --> 00:12:10,429 So what are the comparison groups I might use to try to get there? 211 00:12:10,429 --> 00:12:10,529 Well, I've got experimental interventions versus control. 212 00:12:10,529 --> 00:12:10,663 Sometimes I'm in my epidemiology land. be superior. 213 00:12:10,663 --> 00:12:13,365 So kind of gives me this huge area to be 214 00:12:15,901 --> 00:12:19,271 So what are the comparison groups I might use to try to get there? 215 00:12:20,072 --> 00:12:23,676 Well, I've got experimental interventions versus control 216 00:12:24,376 --> 00:12:27,213 sometimes I'm in my epidemiology land. 217 00:12:27,213 --> 00:12:29,348 I also have cases versus control. 218 00:12:29,348 --> 00:12:31,450 Just because it's a controlled group 219 00:12:31,450 --> 00:12:34,653 doesn't mean you actually have a randomized control arm. 220 00:12:34,653 --> 00:12:37,456 Sometimes I'm comparing the exposed to the unexposed. 221 00:12:37,456 --> 00:12:42,394 So at the World Trade Center sites, they actually took people who were doing 222 00:12:42,394 --> 00:12:46,632 cleanup there who had been exposed to that work and compared them 223 00:12:46,632 --> 00:12:51,570 to a group of people not doing cleanup, who did not have that exposure. 224 00:12:52,505 --> 00:12:57,810 So that is a study that the Center for Disease Control and Prevention 225 00:12:57,810 --> 00:12:59,044 has been running. 226 00:12:59,044 --> 00:13:04,150 We may have various levels of exposure that we want to compare. 227 00:13:04,150 --> 00:13:05,551 Men versus women. 228 00:13:05,551 --> 00:13:09,221 Common comparison you see. The old versus the young. 229 00:13:09,221 --> 00:13:12,892 Maybe BMI that's over 25 to 25 and under. 230 00:13:12,892 --> 00:13:16,962 You have the usual or standard of care or practice. 231 00:13:16,962 --> 00:13:20,699 Standard of care, not always that standardized, by the way, though. 232 00:13:20,699 --> 00:13:23,769 And sometimes we're doing this history. Sometimes I do pre-post. 233 00:13:23,769 --> 00:13:26,539 I take somebody's baseline measures, I intervene on them, 234 00:13:26,539 --> 00:13:28,374 and I look at them afterwards. 235 00:13:28,374 --> 00:13:30,543 Or maybe it's even just natural history. 236 00:13:30,543 --> 00:13:35,147 I look at them when I diagnose them, and I see how they've changed over 237 00:13:35,147 --> 00:13:37,316 the next 12 months or two years. 238 00:13:39,819 --> 00:13:42,154 When you talk about placebos, standard 239 00:13:42,154 --> 00:13:46,759 of care, attention controls, you might have some type of experimental treatment 240 00:13:46,759 --> 00:13:51,397 that you might offer, say, supportive care or some other current treatment. 241 00:13:51,397 --> 00:13:54,099 So supportive care is not no care. 242 00:13:54,099 --> 00:13:56,001 It's not a true placebo. 243 00:13:56,001 --> 00:14:01,040 But if you have a yoga intervention, what should your control group be? 244 00:14:01,040 --> 00:14:02,942 Maybe it's exercise or stretching. 245 00:14:02,942 --> 00:14:07,980 Maybe it's cooking class because you kind of want people in a group 246 00:14:07,980 --> 00:14:10,683 but not really interacting with each other. 247 00:14:11,383 --> 00:14:15,287 Maybe it's a book club because you want them to 248 00:14:15,287 --> 00:14:18,791 actually go someplace and be someplace for 90 minutes. 249 00:14:18,791 --> 00:14:20,326 Maybe you do nothing. 250 00:14:20,326 --> 00:14:24,230 Maybe you say, in fact, again, proof of concept trial. 251 00:14:24,230 --> 00:14:27,333 Does anything change if they go to yoga? 252 00:14:27,333 --> 00:14:28,901 Sometimes we'll do something 253 00:14:28,901 --> 00:14:33,973 called a weightless control where we say, "We want you to do nothing 254 00:14:33,973 --> 00:14:39,011 new for the next 12 weeks." And then you can do the yoga. 255 00:14:39,812 --> 00:14:42,181 The controls cost money. 256 00:14:42,181 --> 00:14:47,453 You will see in the sample size lecture, you have much higher sample sizes 257 00:14:47,453 --> 00:14:49,321 when we have control arms. 258 00:14:49,321 --> 00:14:51,190 You want to control everything 259 00:14:51,190 --> 00:14:55,294 except the smallest element of the intervention you want to test. 260 00:14:55,294 --> 00:14:59,031 Be careful, however, it's not too small of a difference. 261 00:14:59,031 --> 00:15:03,903 So I have this one meditation study, and they really wanted to test 262 00:15:03,903 --> 00:15:04,670 the mindfulness 263 00:15:04,670 --> 00:15:08,774 aspect of meditation, and control for everything else about the meditation. 264 00:15:09,875 --> 00:15:14,179 This is a very small difference and very hard to do. 265 00:15:14,179 --> 00:15:19,652 Like, why don't you just test like the meditation as a whole versus something. 266 00:15:19,652 --> 00:15:23,155 But they're consequences when you have more control imposed. 267 00:15:23,155 --> 00:15:25,491 You can have larger sample sizes. 268 00:15:25,491 --> 00:15:27,459 You may miss a difference. 269 00:15:27,459 --> 00:15:33,699 And if you have a less sensitive outcome measure, you may not pick that difference up. 270 00:15:34,800 --> 00:15:36,368 So plan accordingly. 271 00:15:36,368 --> 00:15:38,304 What are the differences? 272 00:15:38,304 --> 00:15:43,342 Again, you've got to think about every single difference between your study arms 273 00:15:43,342 --> 00:15:45,277 is basically defining your intervention. 274 00:15:45,277 --> 00:15:49,548 If somebody is spending one hour a week with your study 275 00:15:49,548 --> 00:15:54,186 participants versus three hours a week, that is something that is different. 276 00:15:54,186 --> 00:15:59,992 If you tell people to spend 15 minutes at home working on that meditation versus 277 00:15:59,992 --> 00:16:05,864 60 minutes a day at home working on it, again, this is defining your intervention. 278 00:16:05,864 --> 00:16:11,070 And so when you say to me, if you just have two study arms against each other, 279 00:16:11,070 --> 00:16:14,773 well I need to figure out if it's the participant contact time 280 00:16:14,773 --> 00:16:19,712 or the time they spend at home, and say, well, one had one hour of contact 281 00:16:19,712 --> 00:16:21,246 and 15 minutes at home 282 00:16:21,246 --> 00:16:25,551 and the other one had three hours of contact and 60 minutes at home. 283 00:16:25,751 --> 00:16:27,686 I can't tease it apart, folks. 284 00:16:27,686 --> 00:16:33,192 You have to plan all of our interventions to figure out if you can tease that out. 285 00:16:35,661 --> 00:16:36,428 So your 286 00:16:36,428 --> 00:16:40,699 control group might be placebo, most widely accepted treatments, standard treatments. 287 00:16:40,699 --> 00:16:44,203 Always make sure that these two bullets are well-defined. 288 00:16:44,203 --> 00:16:48,073 You're going to have to record it during your study. 289 00:16:48,073 --> 00:16:49,641 Most accepted prevention intervention. 290 00:16:49,641 --> 00:16:55,047 Are you going to do an HIV prevention intervention and not talk about condoms? 291 00:16:55,047 --> 00:16:58,150 What is it that you're going to do? 292 00:16:58,150 --> 00:17:01,653 Again, usual care, not all that usual across sites. 293 00:17:01,653 --> 00:17:04,490 You've got to record what it is. 294 00:17:04,490 --> 00:17:07,326 What are the accepted means of detection? 295 00:17:07,326 --> 00:17:09,228 What is that diagnostic test? 296 00:17:09,228 --> 00:17:15,634 If I did that pap smear for cervical cancer, am I going to get the same results 297 00:17:15,634 --> 00:17:19,805 as if I swipe with vinegar and then do the test? 298 00:17:19,805 --> 00:17:20,539 Non-diseased population. 299 00:17:20,539 --> 00:17:25,844 Sometimes we compare disease to a non-disease population, especially to try to figure out 300 00:17:25,844 --> 00:17:26,979 special differences. 301 00:17:26,979 --> 00:17:28,480 All control groups, 302 00:17:28,480 --> 00:17:32,251 especially when you're doing interventional studies, need to be ethical. 303 00:17:32,985 --> 00:17:37,189 If you're going to assign anybody to a group, anyone meeting the study criterion 304 00:17:37,189 --> 00:17:40,192 has to be able to be in any study group. 305 00:17:40,192 --> 00:17:41,660 If that's not the case, 306 00:17:41,660 --> 00:17:46,165 you need to make sure that your randomization can figure that out, and they know 307 00:17:46,165 --> 00:17:50,669 not to randomize people to study arms that will easily be known to kill them. 308 00:17:50,669 --> 00:17:53,005 I set up an algorithm, folks. 309 00:17:53,005 --> 00:17:58,911 I only know as much medicine as you have imparted to me in setting that up. 310 00:17:58,911 --> 00:18:00,012 Your inclusion/exclusion criteria 311 00:18:00,012 --> 00:18:05,551 should keep people from being in study arms that you know are wrong for them. 312 00:18:05,551 --> 00:18:10,355 If you have questions about that, Chuck Natanson actually has a whole lecture 313 00:18:10,355 --> 00:18:14,793 that he talks about mistakes that have been made in randomization. 314 00:18:14,793 --> 00:18:16,762 In standard of care. 315 00:18:16,762 --> 00:18:20,132 Is it really standard? Good controls cannot always be masked. 316 00:18:20,132 --> 00:18:24,203 Somebody asks me this every year, it is now on the slide. 317 00:18:24,203 --> 00:18:27,606 Try but you may not be able to do it. 318 00:18:27,606 --> 00:18:32,678 People do tend to be better after receiving any type of therapy placebo or not. 319 00:18:32,678 --> 00:18:33,345 Care matters. 320 00:18:33,345 --> 00:18:37,082 Do not underestimate that when you are planning your trials. 321 00:18:37,082 --> 00:18:38,784 Comparing population incidence rates 322 00:18:38,784 --> 00:18:43,522 to the beginning of programs does not take into account a lot of factors. 323 00:18:43,522 --> 00:18:47,226 So, I had someone, they're like, oh, well just do pre-post. 324 00:18:48,660 --> 00:18:52,264 Well, if you had taken into account the control 325 00:18:52,264 --> 00:18:57,035 group, in fact, while they're pre-post, the post looked worse than baseline. 326 00:18:57,035 --> 00:19:00,239 Everybody else looked a lot worse than that. 327 00:19:00,239 --> 00:19:05,010 So, if you hadn't had that control arm, you wouldn't have known 328 00:19:05,010 --> 00:19:07,813 that they actually basically salvaged the slides. 329 00:19:07,813 --> 00:19:11,416 So, everybody else is kind of going like this. 330 00:19:11,416 --> 00:19:12,985 They're all going downhill. 331 00:19:12,985 --> 00:19:18,190 And they kind of -- they went down but not by as much. 332 00:19:18,190 --> 00:19:20,359 It's important to understand this. 333 00:19:20,359 --> 00:19:24,496 No control group. You've got a lot of problems. 334 00:19:24,496 --> 00:19:25,898 Researchers and participants 335 00:19:25,898 --> 00:19:30,002 tend to interpret findings in favor of new treatments. 336 00:19:30,002 --> 00:19:34,573 There's investigator and participant bias when you don't have randomization. 337 00:19:34,573 --> 00:19:37,309 You cannot distinguish effect and time. 338 00:19:37,309 --> 00:19:42,814 If I wait 10-14 days, we will all get over our colds. 339 00:19:42,814 --> 00:19:45,551 So what's the right control group? 340 00:19:45,551 --> 00:19:48,287 There is no right control group. 341 00:19:48,287 --> 00:19:51,056 You just have to choose one. 342 00:19:51,056 --> 00:19:54,259 Also again, remember control groups may happen in nonrandomized studies. 343 00:19:54,259 --> 00:19:56,662 We'll talk more about this next week. 344 00:19:56,662 --> 00:19:59,398 But you have to consider all your effects. 345 00:19:59,398 --> 00:20:01,967 Positive, negative. Are your effects going to plateau? 346 00:20:01,967 --> 00:20:05,504 When do I measure things? Are you looking at long-term differences? 347 00:20:05,504 --> 00:20:07,406 Is it going to be that, 348 00:20:07,406 --> 00:20:12,878 you know, you're going to see a change and then it's going to kind of trickle away? 349 00:20:12,878 --> 00:20:13,512 Delayed response. 350 00:20:13,512 --> 00:20:17,683 Do I have to wait six months before I actually see a change? 351 00:20:18,650 --> 00:20:23,155 You got to consider all this stuff when you're planning a trial. 352 00:20:23,155 --> 00:20:26,592 So time is my favorite confounder in uncontrolled studies. 353 00:20:26,592 --> 00:20:30,062 You've got differential dropout between the study arms. Different seasons. 354 00:20:30,062 --> 00:20:34,199 So if you are trying to test and see different histamine levels, 355 00:20:34,199 --> 00:20:39,037 that is going to vary depending on the season that you are measuring people. 356 00:20:39,037 --> 00:20:41,106 Bone density changes throughout the year. 357 00:20:41,106 --> 00:20:47,412 You've got to make sure you measure them on the 12-month mark, not nine months. 358 00:20:47,412 --> 00:20:49,781 Social support has an issue. 359 00:20:49,781 --> 00:20:53,318 Just empathy and talking to people, really matters. Exercise 360 00:20:53,318 --> 00:20:58,056 we know controls stress, cardiovascular risk factors, a lot of other issues. 361 00:20:58,056 --> 00:21:01,193 You see immune responses with all of these. 362 00:21:01,193 --> 00:21:03,161 So what's your study about? 363 00:21:03,161 --> 00:21:06,698 What do you need to control and not control? 364 00:21:07,499 --> 00:21:10,235 Masking can help, especially masking outcome assessors. 365 00:21:10,235 --> 00:21:16,141 When in doubt, when you can mask nobody else, mask the people collecting your data. 366 00:21:16,141 --> 00:21:19,311 Mask them to the hypotheses of the study. 367 00:21:20,612 --> 00:21:21,580 But you need 368 00:21:21,580 --> 00:21:25,684 to specify in your protocols who is masked, why, how, and to what. 369 00:21:25,684 --> 00:21:29,821 If I break my ankle, and I'm in a medical products study, actually 370 00:21:29,821 --> 00:21:34,559 the PI of the study may not need to know what study arm I'm in. 371 00:21:34,559 --> 00:21:36,762 The safety officer might need to know. 372 00:21:36,762 --> 00:21:37,729 The person doing 373 00:21:37,729 --> 00:21:42,467 my surgery might need to know to see if they have to adjust my anesthesia. 374 00:21:43,201 --> 00:21:46,038 But realistically, I don't need to know. 375 00:21:46,038 --> 00:21:49,308 A lot of people don't need to know. 376 00:21:49,308 --> 00:21:54,546 Everything about blinding is this idea -- it's like playing like secret spy. 377 00:21:54,546 --> 00:21:56,982 It's need to know information. 378 00:21:56,982 --> 00:22:01,053 All studies should be reproducible, regardless of your study 379 00:22:01,053 --> 00:22:03,088 design, regardless of your study. 380 00:22:03,088 --> 00:22:06,725 You need a well-defined study population. Well-defined inclusion/exclusion criteria. 381 00:22:06,725 --> 00:22:12,798 If I had seven people in this room, you should all decide the same thing 382 00:22:12,964 --> 00:22:16,268 if subject A should be in or out of the study. 383 00:22:16,268 --> 00:22:18,337 It needs to be well understood. 384 00:22:18,337 --> 00:22:21,606 The study conduct -- well, someone's having fun out back. 385 00:22:21,606 --> 00:22:23,408 Study conduct needs to be well-described. 386 00:22:23,408 --> 00:22:25,777 How are you going to do your study? 387 00:22:25,777 --> 00:22:28,780 And if somebody is injured and has to leave quickly, 388 00:22:28,780 --> 00:22:34,119 someone else's got to walk in, are they going to walk in and do it the same way? 389 00:22:34,119 --> 00:22:35,220 And that's everyone, 390 00:22:35,220 --> 00:22:38,323 from your nurse coordinators to your statisticians to your data managers. 391 00:22:38,323 --> 00:22:41,760 You have to know that the labs are going to be processed 392 00:22:41,760 --> 00:22:46,565 the same way, that you're going to go and try to get people from the same place, 393 00:22:46,565 --> 00:22:50,836 and then every little step of that study is going to follow the same way. 394 00:22:50,836 --> 00:22:53,038 Can I reproduce the outcome measures? 395 00:22:53,038 --> 00:22:56,141 How are you collecting those? How are you doing it? 396 00:22:56,141 --> 00:23:00,178 We'll talk more about that later and also that data and analyses. 397 00:23:00,178 --> 00:23:00,812 There're 398 00:23:00,812 --> 00:23:05,784 a lot of potential biases in clinical trials, and there are a lot of potential remedies. 399 00:23:05,784 --> 00:23:10,422 So think about these if somebody says, "Oh, here's a problem." Well, try to find 400 00:23:10,422 --> 00:23:11,056 your solution. 401 00:23:13,492 --> 00:23:14,793 And you also have 402 00:23:14,793 --> 00:23:19,431 to think we all have the bias of who's actually in the study, anyway. 403 00:23:19,431 --> 00:23:23,402 You are trying to generalize to this big, lighter box over here. 404 00:23:23,402 --> 00:23:26,071 But realistically, you've got those that are interested 405 00:23:26,071 --> 00:23:29,374 in participating, meet the criteria, consent, and then get randomized. 406 00:23:29,374 --> 00:23:35,313 It's a much smaller group and it may not be as representative as you'd like it to be. 407 00:23:35,313 --> 00:23:39,618 But that's part of why it's really hard work to be a trialist. 408 00:23:40,952 --> 00:23:46,558 All of our studies aren't gold, but we can sure try for it. 409 00:23:46,558 --> 00:23:49,561 So some conclusions in the next minute-and-a-half. 410 00:23:49,561 --> 00:23:51,263 What is the question? 411 00:23:51,263 --> 00:23:53,832 You've got population or disease, P. 412 00:23:53,832 --> 00:23:56,401 So some people call it PICO. 413 00:23:56,401 --> 00:23:58,136 Some call it PICO(T). 414 00:23:58,136 --> 00:24:03,708 The intervention or variable of interest, the comparison group, your outcome, and time. 415 00:24:03,708 --> 00:24:06,711 And you want to write this sentence. 416 00:24:07,612 --> 00:24:12,918 This is an example, like, in this population, how does this intervention or variable 417 00:24:12,918 --> 00:24:17,856 of interest compare to this control influence the outcome during this time period. 418 00:24:17,856 --> 00:24:20,525 Phrase every single study question like this. 419 00:24:20,525 --> 00:24:22,427 This is your study summary. 420 00:24:22,427 --> 00:24:28,500 When I ask you for a one sentence summary of your study, write it like this. 421 00:24:28,500 --> 00:24:33,038 And if you cannot fill in those letters, you have a problem. 422 00:24:34,306 --> 00:24:35,273 The other part 423 00:24:35,273 --> 00:24:39,778 of your study question is who cares about your study question, other than you? 424 00:24:39,778 --> 00:24:44,616 Your question is always going to come first, but you've got to consider the questions 425 00:24:44,616 --> 00:24:48,153 you want to ask, those hypotheses that you're trying to test, 426 00:24:48,153 --> 00:24:51,356 because I've got to turn your question into something testable. 427 00:24:51,356 --> 00:24:54,259 What are the key factors you've got to control? 428 00:24:54,259 --> 00:24:57,662 Those ethical issues and constraints? What can be said? 429 00:24:57,662 --> 00:25:02,200 Maybe you need multiple control groups in order to actually answer your 430 00:25:02,200 --> 00:25:03,301 questions of interest.