Baseline iPRGC activity (cells in the back of the eye as measured by blue light-driven inputs to the pupil response - measured by the blue decay coefficient). The Blue Decay Coefficient represents the rate at which the pupil redilates in the dark after exposure to multiple 5-second pulses of red and blue light. The redilation data are fit by an exponential decay function eβt where t is time in seconds and the coefficient β is the natural log of the percent change in pupil diameter per second. Values range from -0.30 to -0.01. More positive values represent slower pupil redilation and are associated with greater, potentially beneficial ipRGC activity.

Testing the hypothesis that long-term soft bifocal contact lens wear does not alter accommodative lag. This hypothesis predicts that at the baseline BLINK2 Study visit, the accommodative lag will be similar across the three treatment groups that were randomly assigned at the beginning of the BLINK Study (NCT02255474). Assessed data from the beginning of the BLINK Study up to the BLINK2 Study Baseline Visit approximately 4.7 years, BLINK2 Study Baseline Visit reported.

Testing the hypothesis that long-term soft bifocal contact lens wear does not alter accommodative facility. This hypothesis predicts that at the baseline BLINK2 Study visit, the accommodative lag will be similar across the three treatment groups that were randomly assigned at the beginning of the BLINK Study (NCT02255474). Assessed data from the beginning of the BLINK Study up to the BLINK2 Study Baseline Visit approximately 4.7 years, BLINK2 Study Baseline Visit reported.

Test the hypothesis that wearing +2.50 D multifocal contact lenses slow rather than merely delay myopia progression. This null hypothesis predicts that during the first two years of the BLINK2 Study, when all subjects will wear +2.50 D multifocal contact lenses, axial length elongation at the same rate regardless of original lens assignment (i.e., +2.50 D multifocal lenses, +1.50 D multifocal lenses, SVLs). Alternatively, faster myopia progression in subjects originally fitted with soft bifocal contact lenses compared to single vision contact lenses would indicate a delay in myopia progression rather than a permanent treatment benefit. Measured as the change the baseline BLINK2 visit to the 2 year visit on the IOLMaster which is not the entire time frame of the study - as detailed in the specific aims from the funded grant proposal.

Because the exposures before the baseline visit were part of NCT02255474 immediately before this cohort, the original groups were analyzed.

The investigators will test the hypothesis that there is no increase in myopia when switching from +2.50 D multifocal contact lenses to single vision contact lenses in Year 2 of the BLINK2 observational study. This hypothesis predicts that the progression of myopia during the last year of follow-up when all subjects will switch to single vision contact lenses, will be similar to myopia progression during the first two years when all subjects wore multifocal contact lenses. Alternatively, faster progression after switching to single vision contact lens wear indicates a "rebound" of myopia progression.

This aim was specifically designed to measure what happened between the 2nd and 3rd annual visit which is not the entire time frame of the study - as detailed in the specific aims from the funded grant proposal. Because the entire cohort was wearing the same contact lens, it uses all participants together.

The investigators will test the hypothesis that there is no increase in myopia, as measured by the change in the spherical equivalent, when switching from +2.50 D multifocal contact lenses to single vision contact lenses in Year 2 of the BLINK2 observational study. This hypothesis predicts that the progression of myopia during the last year of follow-up when all subjects will switch to single vision contact lenses, will be similar to myopia progression during the first two years when all subjects wore multifocal contact lenses. Alternatively, faster progression after switching to single vision contact lens wear indicates a "rebound" of myopia progression.

This aim was specifically designed to measure what happened between the 2nd and 3rd annual visit which is not the entire time frame of the study - as detailed in the specific aims from the funded grant proposal. Because the entire cohort was wearing the same contact lens, it uses all participants together.

Test the hypothesis that wearing +2.50 D multifocal contact lenses slow rather than merely delay myopia progression. This null hypothesis predicts that during the first two years of the BLINK2 Study, when all subjects will wear +2.50 D multifocal contact lenses, participants will have myopia progression, as measured by spherical equivalent, at the same rate regardless of original lens assignment (i.e., +2.50 D multifocal lenses, +1.50 D multifocal lenses, SVLs). Alternatively, faster myopia progression in those with soft bifocal contact lenses compared to SVLs would indicate a delay in myopia progression rather than a permanent treatment benefit.

Measured between Baseline and Year 2 of the BLINK2 Study which is not the entire time frame of the study - as detailed in the specific aims from the funded grant proposal.

Because the exposures before the baseline visit were part of NCT02255474 immediately before this cohort, the original groups were analyzed.

Participants assigned to Single Vision CL group in BLINK Randomized Control Trial/ In BLINK2 Observational Study Baseline to Year 2: +2.50 D/Year 2 to Year 3: Single Vision Contact Lenses

Total of all reporting groups

Sphere + cylinder/2 from cycloplegic autorefraction

Axial length as measured by the IOLMaster

test the hypothesis that less ipRGC activity (cells in the back of the eye as measured by blue light-driven inputs to the pupil response - measured by the blue decay coefficient) as measured at the Baseline BLINK 2 is associated with greater axial elongation (eye growth) over three years

The hypothesis relates to the two years of multifocal contact lens wear and one year of single vision contact lens wear. As such, it uses the entire sample which experiences the same contact lens wear in the BLINK2 Study.

Axial length average over right and left eye

test the hypothesis that exposure to light levels over 1000 lux as measured at the Baseline BLINK2 visit is associated with less axial elongation (eye growth) over three years

The hypothesis relates to the two years of multifocal contact lens wear and one year of single vision contact lens wear. As such, it uses the entire sample which experiences the same contact lens wear in the BLINK2 Study.

Axial length measured as the average of the right and left eye.

The three-year change from baseline to three years for choroidal thickness.

Right eye only

Baseline light exposure as measured by minutes at light levels over 1000 lux. Light exposure was monitored using the Actiwatch2 (Phillips Respironics), a light-sensing and logging watch worn on the wrist. Participants wore the device for a 1 week period to monitor environmental light exposure. The illuminance was measured in lux every minute. Data were scrubbed of periods where the watch was not worn or other artifacts. Light levels over 1000 lux were added to determine time outdoors in minutes.

exposure received by both eyes

Baseline iPRGC activity (cells in the back of the eye as measured by blue light-driven inputs to the pupil response - measured by the blue decay coefficient). The Blue Decay Coefficient represents the rate at which the pupil redilates in the dark after exposure to multiple 5-second pulses of red and blue light. The redilation data are fit by an exponential decay function eβt where t is time in seconds and the coefficient β is the natural log of the percent change in pupil diameter per second. Values range from -0.30 to -0.01. More positive values represent slower pupil redilation and are associated with greater, potentially beneficial ipRGC activity.

Right eyes

Testing the hypothesis that long-term soft bifocal contact lens wear does not alter accommodative amplitude. This hypothesis predicts that at the baseline BLINK2 Study visit, the accommodative amplitude will be similar across the three treatment groups that were randomly assigned at the beginning of the BLINK Study (NCT02255474). Assessed data from the beginning of the BLINK Study up to the BLINK2 Study Baseline Visit approximately 4.7 years, BLINK2 Study Baseline Visit reported

Right eyes of participants. Using method of Anderson and Stuebing. Anderson HA, Stuebing KK. Subjective versus Objective Accommodative Amplitude: Preschool to Presbyopia. Optom Vis Sci 2014;91:1290-301.

Testing the hypothesis that long-term soft bifocal contact lens wear does not alter accommodative lag. This hypothesis predicts that at the baseline BLINK2 Study visit, the accommodative lag will be similar across the three treatment groups that were randomly assigned at the beginning of the BLINK Study (NCT02255474). Assessed data from the beginning of the BLINK Study up to the BLINK2 Study Baseline Visit approximately 4.7 years, BLINK2 Study Baseline Visit reported.

Right eyes analyzed. near point rod with a card containing 2.06 M (20/125 Snellen equivalent) was placed at 33 cm (a 3D accommodative stimulus) in front of the right eye while the contralateral eye was occluded. The participant was encouraged to keep the letters clear until at least five valid readings were obtained. The average spherical equivalent was added to 3 (the accommodative stimulus), so accommodative lag is positive and accommodative lead is negative.

Testing the hypothesis that long-term soft bifocal contact lens wear does not alter accommodative facility. This hypothesis predicts that at the baseline BLINK2 Study visit, the accommodative lag will be similar across the three treatment groups that were randomly assigned at the beginning of the BLINK Study (NCT02255474). Assessed data from the beginning of the BLINK Study up to the BLINK2 Study Baseline Visit approximately 4.7 years, BLINK2 Study Baseline Visit reported.

The participant focused on a 20/32 letter on the card, and +2.00-D lenses and -2.00 D lenses using flippers. The accommodative facility was recorded as the number of times the participant cleared the letters (flips), divided by two to yield cycles per minute to the nearest 0.5 cycles.

Test the hypothesis that wearing +2.50 D multifocal contact lenses slow rather than merely delay myopia progression. This null hypothesis predicts that during the first two years of the BLINK2 Study, when all subjects will wear +2.50 D multifocal contact lenses, axial length elongation at the same rate regardless of original lens assignment (i.e., +2.50 D multifocal lenses, +1.50 D multifocal lenses, SVLs). Alternatively, faster myopia progression in subjects originally fitted with soft bifocal contact lenses compared to single vision contact lenses would indicate a delay in myopia progression rather than a permanent treatment benefit. Measured as the change the baseline BLINK2 visit to the 2 year visit on the IOLMaster which is not the entire time frame of the study - as detailed in the specific aims from the funded grant proposal.

Because the exposures before the baseline visit were part of NCT02255474 immediately before this cohort, the original groups were analyzed.

Right and left eyes averaged

The investigators will test the hypothesis that there is no increase in myopia when switching from +2.50 D multifocal contact lenses to single vision contact lenses in Year 2 of the BLINK2 observational study. This hypothesis predicts that the progression of myopia during the last year of follow-up when all subjects will switch to single vision contact lenses, will be similar to myopia progression during the first two years when all subjects wore multifocal contact lenses. Alternatively, faster progression after switching to single vision contact lens wear indicates a "rebound" of myopia progression.

This aim was specifically designed to measure what happened between the 2nd and 3rd annual visit which is not the entire time frame of the study - as detailed in the specific aims from the funded grant proposal. Because the entire cohort was wearing the same contact lens, it uses all participants together.

Right and left eye averaged

The investigators will test the hypothesis that there is no increase in myopia, as measured by the change in the spherical equivalent, when switching from +2.50 D multifocal contact lenses to single vision contact lenses in Year 2 of the BLINK2 observational study. This hypothesis predicts that the progression of myopia during the last year of follow-up when all subjects will switch to single vision contact lenses, will be similar to myopia progression during the first two years when all subjects wore multifocal contact lenses. Alternatively, faster progression after switching to single vision contact lens wear indicates a "rebound" of myopia progression.

This aim was specifically designed to measure what happened between the 2nd and 3rd annual visit which is not the entire time frame of the study - as detailed in the specific aims from the funded grant proposal. Because the entire cohort was wearing the same contact lens, it uses all participants together.

Right and left eye averaged

Test the hypothesis that wearing +2.50 D multifocal contact lenses slow rather than merely delay myopia progression. This null hypothesis predicts that during the first two years of the BLINK2 Study, when all subjects will wear +2.50 D multifocal contact lenses, participants will have myopia progression, as measured by spherical equivalent, at the same rate regardless of original lens assignment (i.e., +2.50 D multifocal lenses, +1.50 D multifocal lenses, SVLs). Alternatively, faster myopia progression in those with soft bifocal contact lenses compared to SVLs would indicate a delay in myopia progression rather than a permanent treatment benefit.

Measured between Baseline and Year 2 of the BLINK2 Study which is not the entire time frame of the study - as detailed in the specific aims from the funded grant proposal.

Because the exposures before the baseline visit were part of NCT02255474 immediately before this cohort, the original groups were analyzed.

Right and left eyes averaged

Participants assigned to +1.50 D multiple contact lens (MCL) group in BLINK, in +2.50 D in BLINK2

Participants assigned to SVL group in BLINK, in +2.50 D in BLINK2

Persistent headaches, no cause found

attempted suicide