The glasses Barney is wearing in Dr. Stangel's office are The Sensory Deprivator 5000 that Ted invented in the season 2 episode Monday Night Football.
There is a countdown throughout the episode - from 50 to 1. The countdown is as follows: 50 - On a pamphlet in the Doctor's office in the first scene 49 - Same pamphlet on the Doctor's desk ("months later" according to Ted) 48 - Label on hot sauce Marshall uses at MacLaren's 47 - Barney's laser tag forms are for the "47th Annual" Laser Tag Competition 46 - Printed on Dr. Stangel's certificate behind Lily when they first meet 45 - 45¢ the price of the hot wings at MacLaren's 44 - Number of beers on tap, on a circular blackboard in MacLaren's 44 - (appears twice) Football number on a man's jersey in MacLaren's 43 - On the pamphlet Marshall is reading in Dr. Stangel's office 42 - Second side of the same pamphlet 41 - Race car poster number in Dr. Stangel's office (which disappears when Marshall goes back) 40 - Ted's book that "New York's 40 greatest landmarks" when Robin comes home from Day 1 39 - Number of office behind Robin 38 - On the back of Robin's co-worker's newspaper, 38° in the weather section 37 - Lily is reading a Decadence magazine with the "37 Recipes for Holiday leftovers" title on it. 36 - The number on Marshall's dad's beer, "Old Number 36" 35,34 - Stock markets are up 35.34 points on Robin's news screen 33 - Miners rescued from collapsed mine on Robin's news screen 32-27 - On Robin's screen: "Today's lottery numbers are 32 31 30 29 28 27" 26 - Marshall's dad is reading "26 Home Improvement Shortcuts" 25 - Textbook that Ted is reading in the apartment, "25 Greatest Bridges" 24 - One of Robin's co-workers is reading a magazine, with a sports player on the front with "24" on his jersey 23 - Metro News 23, the channel Robin says "I'm a dirty, dirty girl" on 22 - Seen in the corner of Robin's Japanese broadcast 21 - Calendar behind Dr. Stangel 20 - Room for masturbation room at Dr. Stangel's office 19 - "Top 19 Nekkid girls countdown" on Nekkid magazine in the room 18 - Apartment number of Marshall and Lily's apartment 17,16 - Marshall's specimen cup seen in his apartment 15 - Grams of fiber in Robin's cereal 14,13 - Apartment number of Sandy's apartment 12 - The book "12 days of Christmas" behind Marshall when he's speaking with his parents in their apartment 11- On Ted's architecture book, "America's 11 greatest water towers" 10 - On Robin Sparkles left jacket arm when shown to co-workers by Robin 9 - Disguised Barney holds a folder when talking to Marshall 8 - Number on Dr. Stangel's door 7 - Number on Marshall's champagne bottle 6 - Dr. Stangel turns the folder with the 9 on it upside down 5 - Barney gives Marshall a "Fertility 5" 4 - The "4 Layers of the Uterus" poster in Dr. Stangel's office 3 - "Open til 3 am sign" outside MacLaren's 2 - Clock in Marvin Sr's wood shop 1 - Number of the cab Lily arrives in
In the episode "Bad News," the only number that does not appear onscreen as a numeral is the number 5. Instead, between the numbers 6 and 4, Barney and Marshall share a high five.
Neil Patrick Harris is credited twice for this episode, once in the opening as a member of the main cast and once at the end as "Dr. John Stangel."