Comparison of dry eye symptom relief with SYSTANE® PRO and Artelac® Complete lubricating eye drops

INTERVENTION: Participants self‐apply SYSTANE® PRO preservative‐free eye drops at a location of their choice, 1‐2 drops, 2 times a day for 4 weeks. Ocular surface symptoms and signs are collected at baseline and after 4 weeks. After 4 weeks participants crossover to self‐apply Artelac® Complete preservative‐free eye drops, 1‐2 drops, 4 times a day, at a location of their choice, for a further 4 weeks after which time ocular surface symptoms and signs are again collected. There is no washout period in between. Participant diaries are used throughout to record compliance, and for each product, bottles are collected after 4 weeks' use and weights compared, pre and post‐study, as a further measure of compliance. CONDITION: Dry eye disease; ; Dry eye disease Eye ‐ Diseases / disorders of the eye PRIMARY OUTCOME: Ocular surface symptom score[Ocular Surface Disease Index (validated dry eye symptom questionnaire) Baseline and after 4 weeks of daily application of each eye drop (i.e. at baseline, at 4 weeks (after drop 1) and at 8 weeks (after drop 2), 2 times daily for SYSTANE® PRO and 4 times daily for Artelac® Complete.] INCLUSION CRITERIA: • Age equal to or greater than 18 years • Minimum of 6 months history of self‐reported dry eye • Dry eye diagnosis according to the Tear Film and Ocular Surface Society Dry Eye Workshop III (TFOS DEWS III) diagnostic criteria (6‐item Ocular Surface Disease Inde X(OSDI‐6) score of greater or equal to 4 plus any one or more of the following signs: Non‐invasive tear breakup time (NIBUT) less than 10 seconds, hyperomsomolarity of greater than or equal to 308mOsm/L or an interocular difference in osmolarity of greater than 8 mOsm/L; corneal fluorescein staining of more than 5 corneal spots, conjunctival lissamine green staining of more than 9 conjunctival spots, or lid wiper epitheliopathy of greater than or equal to 2mm in length and greater than or equal to 25% sagittal width). SECONDARY OUTCOME: Blink completeness[Proportion of incomplete blinks observed within a 30 second infrared video recording with the Oculus Keratograph 5M Baseline and 4 weeks after daily application of each eye drop (i.e. at baseline, at 4 weeks (after drop 1) and at 8 weeks (after drop 2).] Blink rate[Blink count within a 30 second period of infrared video recording with the Oculus Keratograph 5M Baseline and 4 weeks after daily application of each eye drop (i.e. at baseline, at 4 weeks (after drop 1) and at 8 weeks (after drop 2), 2 times daily for SYSTANE® PRO and 4 times daily for Artelac® Complete.] Bulbar conjunctival hyperaemia[Objective score of eye redness, on the 0 to 4 Jenvis scale, using the Oculus Keratograph 5M Baseline and 4 weeks after daily application of each eye drop (i.e. at baseline, at 4 weeks (after drop 1) and at 8 weeks (after drop 2), 2 times daily for SYSTANE® PRO and 4 times daily for Artelac® Complete.] Duration of symptom relief after drop application[Participants will log average number of hours of symptom relief provided by the drops on a daily basis via a supplied patient diary. Baseline and after 4 weeks of daily application of each eye drop (i.e. at baseline, at 4 weeks (after drop 1) and at 8 weeks (after drop 2), 2 times daily for SYSTANE® PRO and 4 times daily for Artelac® Complete.] Lipid layer grade (LLG)[Subjective grading of lipid layer quality according to the modified Keeler‐Guillon lipid grading scale, based on interferometric patterns observed via deidentified videos captured with the Oculus Keratograph 5M. Baseline and after 4 weeks of daily application of each eye drop (i.e. at baseline, at 4 weeks (after drop 1) and at 8 weeks (after drop 2), 2 times daily for SYSTANE® PRO and 4 times daily for Artelac® Complete.] Lipid layer thickness (LLT)[Objective grading of lipid layer thickness with the TearScience LipiView II At baseline and after 4 weeks of daily application of each eye drop (i.e. at baseline, at 4 weeks (after drop 1) and at 8 weeks (after drop 2), 2 times daily for SYSTANE® PRO and 4 times daily for Artelac® Complete.] Non‐invasive breakup time[Non‐invasive Keratograph breakup time (NIKBUT) assessed objectively using the Oculus Keratograph 5M At baseline and after 4 weeks of daily application of each eye drop (i.e. at baseline, at 4 weeks (after drop 1) and at 8 weeks (after drop 2, 2 times daily for SYSTANE® PRO and 4 times daily for Artelac® Complete).] Tear evaporation rate[Calculated from an objective measure of evaporation rate within an eye goggle placed over the eye with a Delfin Eye Vapometer, accounting for skin evaporation Baseline and 4 weeks after daily application of each eye drop (i.e. at baseline, at 4 weeks (after drop 1) and at 8 weeks (after drop 2), 2 times daily for SYSTANE® PRO and 4 times daily for Artelac® Complete.] User preference between products[Participants mark their response on a visual analogue scale anchored by the descriptors: first product (weeks 1‐4) and second product (weeks 5‐8). The central point indicates no preference between the two products. At 8 weeks after baseline (following two consecutive 4 week periods of applying each of the two eye drop products, 2 times daily for SYSTANE® PRO and 4 times daily for Artelac® Complete)] User satisfaction with eye drops[Visual analogue scale anchored by the descriptors: 'extremely satisfied' and 'not satisfied at all' Baseline and after 4 weeks of daily application of each eye drop (i.e. at baseline, at 4 weeks (after drop 1) and at 8 weeks (after drop 2).]